diff --git a/src/Magnum/AbstractShaderProgram.cpp b/src/Magnum/AbstractShaderProgram.cpp
index 2dc68ab42..dd0b01f73 100644
--- a/src/Magnum/AbstractShaderProgram.cpp
+++ b/src/Magnum/AbstractShaderProgram.cpp
@@ -52,7 +52,7 @@ Int AbstractShaderProgram::maxVertexAttributes() {
     return value;
 }
 
-#ifndef MAGNUM_TARGET_GLES2
+#if !defined(MAGNUM_TARGET_GLES2) && !defined(MAGNUM_TARGET_WEBGL)
 Int AbstractShaderProgram::maxAtomicCounterBufferSize() {
     #ifndef MAGNUM_TARGET_GLES
     if(!Context::current()->isExtensionSupported<Extensions::GL::ARB::shader_atomic_counters>())
@@ -133,6 +133,7 @@ Int AbstractShaderProgram::maxImageSamples() {
 #endif
 
 #ifndef MAGNUM_TARGET_GLES2
+#ifndef MAGNUM_TARGET_WEBGL
 Int AbstractShaderProgram::maxCombinedShaderOutputResources() {
     #ifndef MAGNUM_TARGET_GLES
     if(!Context::current()->isExtensionSupported<Extensions::GL::ARB::shader_storage_buffer_object>() || !Context::current()->isExtensionSupported<Extensions::GL::ARB::shader_image_load_store>())
@@ -166,7 +167,6 @@ Long AbstractShaderProgram::maxShaderStorageBlockSize() {
 }
 #endif
 
-#ifndef MAGNUM_TARGET_GLES2
 Int AbstractShaderProgram::maxUniformBlockSize() {
     #ifndef MAGNUM_TARGET_GLES
     if(!Context::current()->isExtensionSupported<Extensions::GL::ARB::uniform_buffer_object>())
@@ -180,9 +180,8 @@ Int AbstractShaderProgram::maxUniformBlockSize() {
 
     return value;
 }
-#endif
 
-#ifndef MAGNUM_TARGET_GLES2
+#ifndef MAGNUM_TARGET_WEBGL
 Int AbstractShaderProgram::maxUniformLocations() {
     #ifndef MAGNUM_TARGET_GLES
     if(!Context::current()->isExtensionSupported<Extensions::GL::ARB::explicit_uniform_location>())
@@ -200,7 +199,6 @@ Int AbstractShaderProgram::maxUniformLocations() {
 }
 #endif
 
-#ifndef MAGNUM_TARGET_GLES2
 Int AbstractShaderProgram::minTexelOffset() {
     #ifndef MAGNUM_TARGET_GLES
     if(!Context::current()->isExtensionSupported<Extensions::GL::EXT::gpu_shader4>())
@@ -410,14 +408,15 @@ void AbstractShaderProgram::uniformImplementationDefault(const GLint location, c
     glUniform1fv(location, count, values);
 }
 
-#ifndef MAGNUM_TARGET_GLES2
+#if !defined(MAGNUM_TARGET_GLES2) && !defined(MAGNUM_TARGET_WEBGL)
 void AbstractShaderProgram::uniformImplementationSSO(const GLint location, const GLsizei count, const GLfloat* const values) {
     glProgramUniform1fv(_id, location, count, values);
 }
 #endif
 
+#ifndef MAGNUM_TARGET_WEBGL
 void AbstractShaderProgram::uniformImplementationDSAEXT_SSOEXT(const GLint location, const GLsizei count, const GLfloat* const values) {
-    #if !defined(CORRADE_TARGET_EMSCRIPTEN) && !defined(CORRADE_TARGET_NACL)
+    #ifndef CORRADE_TARGET_NACL
     glProgramUniform1fvEXT(_id, location, count, values);
     #else
     static_cast<void>(location);
@@ -426,6 +425,7 @@ void AbstractShaderProgram::uniformImplementationDSAEXT_SSOEXT(const GLint locat
     CORRADE_ASSERT_UNREACHABLE();
     #endif
 }
+#endif
 
 void AbstractShaderProgram::setUniform(const Int location, const UnsignedInt count, const Math::Vector<2, Float>* const values) {
     (this->*Context::current()->state().shaderProgram->uniform2fvImplementation)(location, count, values);
@@ -436,14 +436,15 @@ void AbstractShaderProgram::uniformImplementationDefault(const GLint location, c
     glUniform2fv(location, count, values[0].data());
 }
 
-#ifndef MAGNUM_TARGET_GLES2
+#if !defined(MAGNUM_TARGET_GLES2) && !defined(MAGNUM_TARGET_WEBGL)
 void AbstractShaderProgram::uniformImplementationSSO(const GLint location, const GLsizei count, const Math::Vector<2, GLfloat>* const values) {
     glProgramUniform2fv(_id, location, count, values[0].data());
 }
 #endif
 
+#ifndef MAGNUM_TARGET_WEBGL
 void AbstractShaderProgram::uniformImplementationDSAEXT_SSOEXT(const GLint location, const GLsizei count, const Math::Vector<2, GLfloat>* const values) {
-    #if !defined(CORRADE_TARGET_EMSCRIPTEN) && !defined(CORRADE_TARGET_NACL)
+    #ifndef CORRADE_TARGET_NACL
     glProgramUniform2fvEXT(_id, location, count, values[0].data());
     #else
     static_cast<void>(location);
@@ -452,6 +453,7 @@ void AbstractShaderProgram::uniformImplementationDSAEXT_SSOEXT(const GLint locat
     CORRADE_ASSERT_UNREACHABLE();
     #endif
 }
+#endif
 
 void AbstractShaderProgram::setUniform(const Int location, const UnsignedInt count, const Math::Vector<3, Float>* const values) {
     (this->*Context::current()->state().shaderProgram->uniform3fvImplementation)(location, count, values);
@@ -462,14 +464,15 @@ void AbstractShaderProgram::uniformImplementationDefault(const GLint location, c
     glUniform3fv(location, count, values[0].data());
 }
 
-#ifndef MAGNUM_TARGET_GLES2
+#if !defined(MAGNUM_TARGET_GLES2) && !defined(MAGNUM_TARGET_WEBGL)
 void AbstractShaderProgram::uniformImplementationSSO(const GLint location, const GLsizei count, const Math::Vector<3, GLfloat>* const values) {
     glProgramUniform3fv(_id, location, count, values[0].data());
 }
 #endif
 
+#ifndef MAGNUM_TARGET_WEBGL
 void AbstractShaderProgram::uniformImplementationDSAEXT_SSOEXT(const GLint location, const GLsizei count, const Math::Vector<3, GLfloat>* const values) {
-    #if !defined(CORRADE_TARGET_EMSCRIPTEN) && !defined(CORRADE_TARGET_NACL)
+    #ifndef CORRADE_TARGET_NACL
     glProgramUniform3fvEXT(_id, location, count, values[0].data());
     #else
     static_cast<void>(location);
@@ -478,6 +481,7 @@ void AbstractShaderProgram::uniformImplementationDSAEXT_SSOEXT(const GLint locat
     CORRADE_ASSERT_UNREACHABLE();
     #endif
 }
+#endif
 
 void AbstractShaderProgram::setUniform(const Int location, const UnsignedInt count, const Math::Vector<4, Float>* const values) {
     (this->*Context::current()->state().shaderProgram->uniform4fvImplementation)(location, count, values);
@@ -488,14 +492,15 @@ void AbstractShaderProgram::uniformImplementationDefault(const GLint location, c
     glUniform4fv(location, count, values[0].data());
 }
 
-#ifndef MAGNUM_TARGET_GLES2
+#if !defined(MAGNUM_TARGET_GLES2) && !defined(MAGNUM_TARGET_WEBGL)
 void AbstractShaderProgram::uniformImplementationSSO(const GLint location, const GLsizei count, const Math::Vector<4, GLfloat>* const values) {
     glProgramUniform4fv(_id, location, count, values[0].data());
 }
 #endif
 
+#ifndef MAGNUM_TARGET_WEBGL
 void AbstractShaderProgram::uniformImplementationDSAEXT_SSOEXT(const GLint location, const GLsizei count, const Math::Vector<4, GLfloat>* const values) {
-    #if !defined(CORRADE_TARGET_EMSCRIPTEN) && !defined(CORRADE_TARGET_NACL)
+    #ifndef CORRADE_TARGET_NACL
     glProgramUniform4fvEXT(_id, location, count, values[0].data());
     #else
     static_cast<void>(location);
@@ -504,6 +509,7 @@ void AbstractShaderProgram::uniformImplementationDSAEXT_SSOEXT(const GLint locat
     CORRADE_ASSERT_UNREACHABLE();
     #endif
 }
+#endif
 
 void AbstractShaderProgram::setUniform(const Int location, const UnsignedInt count, const Int* const values) {
     (this->*Context::current()->state().shaderProgram->uniform1ivImplementation)(location, count, values);
@@ -514,14 +520,15 @@ void AbstractShaderProgram::uniformImplementationDefault(const GLint location, c
     glUniform1iv(location, count, values);
 }
 
-#ifndef MAGNUM_TARGET_GLES2
+#if !defined(MAGNUM_TARGET_GLES2) && !defined(MAGNUM_TARGET_WEBGL)
 void AbstractShaderProgram::uniformImplementationSSO(const GLint location, const GLsizei count, const GLint* const values) {
     glProgramUniform1iv(_id, location, count, values);
 }
 #endif
 
+#ifndef MAGNUM_TARGET_WEBGL
 void AbstractShaderProgram::uniformImplementationDSAEXT_SSOEXT(const GLint location, const GLsizei count, const GLint* const values) {
-    #if !defined(CORRADE_TARGET_EMSCRIPTEN) && !defined(CORRADE_TARGET_NACL)
+    #ifndef CORRADE_TARGET_NACL
     glProgramUniform1ivEXT(_id, location, count, values);
     #else
     static_cast<void>(location);
@@ -530,6 +537,7 @@ void AbstractShaderProgram::uniformImplementationDSAEXT_SSOEXT(const GLint locat
     CORRADE_ASSERT_UNREACHABLE();
     #endif
 }
+#endif
 
 void AbstractShaderProgram::setUniform(const Int location, const UnsignedInt count, const Math::Vector<2, Int>* const values) {
     (this->*Context::current()->state().shaderProgram->uniform2ivImplementation)(location, count, values);
@@ -540,14 +548,15 @@ void AbstractShaderProgram::uniformImplementationDefault(const GLint location, c
     glUniform2iv(location, count, values[0].data());
 }
 
-#ifndef MAGNUM_TARGET_GLES2
+#if !defined(MAGNUM_TARGET_GLES2) && !defined(MAGNUM_TARGET_WEBGL)
 void AbstractShaderProgram::uniformImplementationSSO(const GLint location, const GLsizei count, const Math::Vector<2, GLint>* const values) {
     glProgramUniform2iv(_id, location, count, values[0].data());
 }
 #endif
 
+#ifndef MAGNUM_TARGET_WEBGL
 void AbstractShaderProgram::uniformImplementationDSAEXT_SSOEXT(const GLint location, const GLsizei count, const Math::Vector<2, GLint>* const values) {
-    #if !defined(CORRADE_TARGET_EMSCRIPTEN) && !defined(CORRADE_TARGET_NACL)
+    #ifndef CORRADE_TARGET_NACL
     glProgramUniform2ivEXT(_id, location, count, values[0].data());
     #else
     static_cast<void>(location);
@@ -556,6 +565,7 @@ void AbstractShaderProgram::uniformImplementationDSAEXT_SSOEXT(const GLint locat
     CORRADE_ASSERT_UNREACHABLE();
     #endif
 }
+#endif
 
 void AbstractShaderProgram::setUniform(const Int location, const UnsignedInt count, const Math::Vector<3, Int>* const values) {
     (this->*Context::current()->state().shaderProgram->uniform3ivImplementation)(location, count, values);
@@ -566,14 +576,15 @@ void AbstractShaderProgram::uniformImplementationDefault(const GLint location, c
     glUniform3iv(location, count, values[0].data());
 }
 
-#ifndef MAGNUM_TARGET_GLES2
+#if !defined(MAGNUM_TARGET_GLES2) && !defined(MAGNUM_TARGET_WEBGL)
 void AbstractShaderProgram::uniformImplementationSSO(const GLint location, const GLsizei count, const Math::Vector<3, GLint>* const values) {
     glProgramUniform3iv(_id, location, count, values[0].data());
 }
 #endif
 
+#ifndef MAGNUM_TARGET_WEBGL
 void AbstractShaderProgram::uniformImplementationDSAEXT_SSOEXT(const GLint location, const GLsizei count, const Math::Vector<3, GLint>* const values) {
-    #if !defined(CORRADE_TARGET_EMSCRIPTEN) && !defined(CORRADE_TARGET_NACL)
+    #ifndef CORRADE_TARGET_NACL
     glProgramUniform3ivEXT(_id, location, count, values[0].data());
     #else
     static_cast<void>(location);
@@ -582,6 +593,7 @@ void AbstractShaderProgram::uniformImplementationDSAEXT_SSOEXT(const GLint locat
     CORRADE_ASSERT_UNREACHABLE();
     #endif
 }
+#endif
 
 void AbstractShaderProgram::setUniform(const Int location, const UnsignedInt count, const Math::Vector<4, Int>* const values) {
     (this->*Context::current()->state().shaderProgram->uniform4ivImplementation)(location, count, values);
@@ -592,14 +604,15 @@ void AbstractShaderProgram::uniformImplementationDefault(const GLint location, c
     glUniform4iv(location, count, values[0].data());
 }
 
-#ifndef MAGNUM_TARGET_GLES2
+#if !defined(MAGNUM_TARGET_GLES2) && !defined(MAGNUM_TARGET_WEBGL)
 void AbstractShaderProgram::uniformImplementationSSO(const GLint location, const GLsizei count, const Math::Vector<4, GLint>* const values) {
     glProgramUniform4iv(_id, location, count, values[0].data());
 }
 #endif
 
+#ifndef MAGNUM_TARGET_WEBGL
 void AbstractShaderProgram::uniformImplementationDSAEXT_SSOEXT(const GLint location, const GLsizei count, const Math::Vector<4, GLint>* const values) {
-    #if !defined(CORRADE_TARGET_EMSCRIPTEN) && !defined(CORRADE_TARGET_NACL)
+    #ifndef CORRADE_TARGET_NACL
     glProgramUniform4ivEXT(_id, location, count, values[0].data());
     #else
     static_cast<void>(location);
@@ -608,6 +621,7 @@ void AbstractShaderProgram::uniformImplementationDSAEXT_SSOEXT(const GLint locat
     CORRADE_ASSERT_UNREACHABLE();
     #endif
 }
+#endif
 
 #ifndef MAGNUM_TARGET_GLES2
 void AbstractShaderProgram::setUniform(const Int location, const UnsignedInt count, const UnsignedInt* const values) {
@@ -619,6 +633,7 @@ void AbstractShaderProgram::uniformImplementationDefault(const GLint location, c
     glUniform1uiv(location, count, values);
 }
 
+#ifndef MAGNUM_TARGET_WEBGL
 void AbstractShaderProgram::uniformImplementationSSO(const GLint location, const GLsizei count, const GLuint* const values) {
     glProgramUniform1uiv(_id, location, count, values);
 }
@@ -626,6 +641,7 @@ void AbstractShaderProgram::uniformImplementationSSO(const GLint location, const
 void AbstractShaderProgram::uniformImplementationDSAEXT_SSOEXT(const GLint location, const GLsizei count, const GLuint* const values) {
     glProgramUniform1uivEXT(_id, location, count, values);
 }
+#endif
 
 void AbstractShaderProgram::setUniform(const Int location, const UnsignedInt count, const Math::Vector<2, UnsignedInt>* const values) {
     (this->*Context::current()->state().shaderProgram->uniform2uivImplementation)(location, count, values);
@@ -636,6 +652,7 @@ void AbstractShaderProgram::uniformImplementationDefault(const GLint location, c
     glUniform2uiv(location, count, values[0].data());
 }
 
+#ifndef MAGNUM_TARGET_WEBGL
 void AbstractShaderProgram::uniformImplementationSSO(const GLint location, const GLsizei count, const Math::Vector<2, GLuint>* const values) {
     glProgramUniform2uiv(_id, location, count, values[0].data());
 }
@@ -643,6 +660,7 @@ void AbstractShaderProgram::uniformImplementationSSO(const GLint location, const
 void AbstractShaderProgram::uniformImplementationDSAEXT_SSOEXT(const GLint location, const GLsizei count, const Math::Vector<2, GLuint>* const values) {
     glProgramUniform2uivEXT(_id, location, count, values[0].data());
 }
+#endif
 
 void AbstractShaderProgram::setUniform(const Int location, const UnsignedInt count, const Math::Vector<3, UnsignedInt>* const values) {
     (this->*Context::current()->state().shaderProgram->uniform3uivImplementation)(location, count, values);
@@ -653,6 +671,7 @@ void AbstractShaderProgram::uniformImplementationDefault(const GLint location, c
     glUniform3uiv(location, count, values[0].data());
 }
 
+#ifndef MAGNUM_TARGET_WEBGL
 void AbstractShaderProgram::uniformImplementationSSO(const GLint location, const GLsizei count, const Math::Vector<3, GLuint>* const values) {
     glProgramUniform3uiv(_id, location, count, values[0].data());
 }
@@ -660,6 +679,7 @@ void AbstractShaderProgram::uniformImplementationSSO(const GLint location, const
 void AbstractShaderProgram::uniformImplementationDSAEXT_SSOEXT(const GLint location, const GLsizei count, const Math::Vector<3, GLuint>* const values) {
     glProgramUniform3uivEXT(_id, location, count, values[0].data());
 }
+#endif
 
 void AbstractShaderProgram::setUniform(const Int location, const UnsignedInt count, const Math::Vector<4, UnsignedInt>* const values) {
     (this->*Context::current()->state().shaderProgram->uniform4uivImplementation)(location, count, values);
@@ -670,6 +690,7 @@ void AbstractShaderProgram::uniformImplementationDefault(const GLint location, c
     glUniform4uiv(location, count, values[0].data());
 }
 
+#ifndef MAGNUM_TARGET_WEBGL
 void AbstractShaderProgram::uniformImplementationSSO(const GLint location, const GLsizei count, const Math::Vector<4, GLuint>* const values) {
     glProgramUniform4uiv(_id, location, count, values[0].data());
 }
@@ -678,6 +699,7 @@ void AbstractShaderProgram::uniformImplementationDSAEXT_SSOEXT(const GLint locat
     glProgramUniform4uivEXT(_id, location, count, values[0].data());
 }
 #endif
+#endif
 
 #ifndef MAGNUM_TARGET_GLES
 void AbstractShaderProgram::setUniform(const Int location, const UnsignedInt count, const Double* const values) {
@@ -758,14 +780,15 @@ void AbstractShaderProgram::uniformImplementationDefault(const GLint location, c
     glUniformMatrix2fv(location, count, GL_FALSE, values[0].data());
 }
 
-#ifndef MAGNUM_TARGET_GLES2
+#if !defined(MAGNUM_TARGET_GLES2) && !defined(MAGNUM_TARGET_WEBGL)
 void AbstractShaderProgram::uniformImplementationSSO(const GLint location, const GLsizei count, const Math::RectangularMatrix<2, 2, GLfloat>* const values) {
     glProgramUniformMatrix2fv(_id, location, count, GL_FALSE, values[0].data());
 }
 #endif
 
+#ifndef MAGNUM_TARGET_WEBGL
 void AbstractShaderProgram::uniformImplementationDSAEXT_SSOEXT(const GLint location, const GLsizei count, const Math::RectangularMatrix<2, 2, GLfloat>* const values) {
-    #if !defined(CORRADE_TARGET_EMSCRIPTEN) && !defined(CORRADE_TARGET_NACL)
+    #ifndef CORRADE_TARGET_NACL
     glProgramUniformMatrix2fvEXT(_id, location, count, GL_FALSE, values[0].data());
     #else
     static_cast<void>(location);
@@ -774,6 +797,7 @@ void AbstractShaderProgram::uniformImplementationDSAEXT_SSOEXT(const GLint locat
     CORRADE_ASSERT_UNREACHABLE();
     #endif
 }
+#endif
 
 void AbstractShaderProgram::setUniform(const Int location, const UnsignedInt count, const Math::RectangularMatrix<3, 3, Float>* const values) {
     (this->*Context::current()->state().shaderProgram->uniformMatrix3fvImplementation)(location, count, values);
@@ -784,14 +808,15 @@ void AbstractShaderProgram::uniformImplementationDefault(const GLint location, c
     glUniformMatrix3fv(location, count, GL_FALSE, values[0].data());
 }
 
-#ifndef MAGNUM_TARGET_GLES2
+#if !defined(MAGNUM_TARGET_GLES2) && !defined(MAGNUM_TARGET_WEBGL)
 void AbstractShaderProgram::uniformImplementationSSO(const GLint location, const GLsizei count, const Math::RectangularMatrix<3, 3, GLfloat>* const values) {
     glProgramUniformMatrix3fv(_id, location, count, GL_FALSE, values[0].data());
 }
 #endif
 
+#ifndef MAGNUM_TARGET_WEBGL
 void AbstractShaderProgram::uniformImplementationDSAEXT_SSOEXT(const GLint location, const GLsizei count, const Math::RectangularMatrix<3, 3, GLfloat>* const values) {
-    #if !defined(CORRADE_TARGET_EMSCRIPTEN) && !defined(CORRADE_TARGET_NACL)
+    #ifndef CORRADE_TARGET_NACL
     glProgramUniformMatrix3fvEXT(_id, location, count, GL_FALSE, values[0].data());
     #else
     static_cast<void>(location);
@@ -800,6 +825,7 @@ void AbstractShaderProgram::uniformImplementationDSAEXT_SSOEXT(const GLint locat
     CORRADE_ASSERT_UNREACHABLE();
     #endif
 }
+#endif
 
 void AbstractShaderProgram::setUniform(const Int location, const UnsignedInt count, const Math::RectangularMatrix<4, 4, Float>* const values) {
     (this->*Context::current()->state().shaderProgram->uniformMatrix4fvImplementation)(location, count, values);
@@ -810,14 +836,15 @@ void AbstractShaderProgram::uniformImplementationDefault(const GLint location, c
     glUniformMatrix4fv(location, count, GL_FALSE, values[0].data());
 }
 
-#ifndef MAGNUM_TARGET_GLES2
+#if !defined(MAGNUM_TARGET_GLES2) && !defined(MAGNUM_TARGET_WEBGL)
 void AbstractShaderProgram::uniformImplementationSSO(const GLint location, const GLsizei count, const Math::RectangularMatrix<4, 4, GLfloat>* const values) {
     glProgramUniformMatrix4fv(_id, location, count, GL_FALSE, values[0].data());
 }
 #endif
 
+#ifndef MAGNUM_TARGET_WEBGL
 void AbstractShaderProgram::uniformImplementationDSAEXT_SSOEXT(const GLint location, const GLsizei count, const Math::RectangularMatrix<4, 4, GLfloat>* const values) {
-    #if !defined(CORRADE_TARGET_EMSCRIPTEN) && !defined(CORRADE_TARGET_NACL)
+    #ifndef CORRADE_TARGET_NACL
     glProgramUniformMatrix4fvEXT(_id, location, count, GL_FALSE, values[0].data());
     #else
     static_cast<void>(location);
@@ -826,6 +853,7 @@ void AbstractShaderProgram::uniformImplementationDSAEXT_SSOEXT(const GLint locat
     CORRADE_ASSERT_UNREACHABLE();
     #endif
 }
+#endif
 
 #ifndef MAGNUM_TARGET_GLES2
 void AbstractShaderProgram::setUniform(const Int location, const UnsignedInt count, const Math::RectangularMatrix<2, 3, Float>* const values) {
@@ -837,6 +865,7 @@ void AbstractShaderProgram::uniformImplementationDefault(const GLint location, c
     glUniformMatrix2x3fv(location, count, GL_FALSE, values[0].data());
 }
 
+#ifndef MAGNUM_TARGET_WEBGL
 void AbstractShaderProgram::uniformImplementationSSO(const GLint location, const GLsizei count, const Math::RectangularMatrix<2, 3, GLfloat>* const values) {
     glProgramUniformMatrix2x3fv(_id, location, count, GL_FALSE, values[0].data());
 }
@@ -844,6 +873,7 @@ void AbstractShaderProgram::uniformImplementationSSO(const GLint location, const
 void AbstractShaderProgram::uniformImplementationDSAEXT_SSOEXT(const GLint location, const GLsizei count, const Math::RectangularMatrix<2, 3, GLfloat>* const values) {
     glProgramUniformMatrix2x3fvEXT(_id, location, count, GL_FALSE, values[0].data());
 }
+#endif
 
 void AbstractShaderProgram::setUniform(const Int location, const UnsignedInt count, const Math::RectangularMatrix<3, 2, Float>* const values) {
     (this->*Context::current()->state().shaderProgram->uniformMatrix3x2fvImplementation)(location, count, values);
@@ -854,6 +884,7 @@ void AbstractShaderProgram::uniformImplementationDefault(const GLint location, c
     glUniformMatrix3x2fv(location, count, GL_FALSE, values[0].data());
 }
 
+#ifndef MAGNUM_TARGET_WEBGL
 void AbstractShaderProgram::uniformImplementationSSO(const GLint location, const GLsizei count, const Math::RectangularMatrix<3, 2, GLfloat>* const values) {
     glProgramUniformMatrix3x2fv(_id, location, count, GL_FALSE, values[0].data());
 }
@@ -861,6 +892,7 @@ void AbstractShaderProgram::uniformImplementationSSO(const GLint location, const
 void AbstractShaderProgram::uniformImplementationDSAEXT_SSOEXT(const GLint location, const GLsizei count, const Math::RectangularMatrix<3, 2, GLfloat>* const values) {
     glProgramUniformMatrix3x2fvEXT(_id, location, count, GL_FALSE, values[0].data());
 }
+#endif
 
 void AbstractShaderProgram::setUniform(const Int location, const UnsignedInt count, const Math::RectangularMatrix<2, 4, Float>* const values) {
     (this->*Context::current()->state().shaderProgram->uniformMatrix2x4fvImplementation)(location, count, values);
@@ -871,6 +903,7 @@ void AbstractShaderProgram::uniformImplementationDefault(const GLint location, c
     glUniformMatrix2x4fv(location, count, GL_FALSE, values[0].data());
 }
 
+#ifndef MAGNUM_TARGET_WEBGL
 void AbstractShaderProgram::uniformImplementationSSO(const GLint location, const GLsizei count, const Math::RectangularMatrix<2, 4, GLfloat>* const values) {
     glProgramUniformMatrix2x4fv(_id, location, count, GL_FALSE, values[0].data());
 }
@@ -878,6 +911,7 @@ void AbstractShaderProgram::uniformImplementationSSO(const GLint location, const
 void AbstractShaderProgram::uniformImplementationDSAEXT_SSOEXT(const GLint location, const GLsizei count, const Math::RectangularMatrix<2, 4, GLfloat>* const values) {
     glProgramUniformMatrix2x4fvEXT(_id, location, count, GL_FALSE, values[0].data());
 }
+#endif
 
 void AbstractShaderProgram::setUniform(const Int location, const UnsignedInt count, const Math::RectangularMatrix<4, 2, Float>* const values) {
     (this->*Context::current()->state().shaderProgram->uniformMatrix4x2fvImplementation)(location, count, values);
@@ -888,6 +922,7 @@ void AbstractShaderProgram::uniformImplementationDefault(const GLint location, c
     glUniformMatrix4x2fv(location, count, GL_FALSE, values[0].data());
 }
 
+#ifndef MAGNUM_TARGET_WEBGL
 void AbstractShaderProgram::uniformImplementationSSO(const GLint location, const GLsizei count, const Math::RectangularMatrix<4, 2, GLfloat>* const values) {
     glProgramUniformMatrix4x2fv(_id, location, count, GL_FALSE, values[0].data());
 }
@@ -895,6 +930,7 @@ void AbstractShaderProgram::uniformImplementationSSO(const GLint location, const
 void AbstractShaderProgram::uniformImplementationDSAEXT_SSOEXT(const GLint location, const GLsizei count, const Math::RectangularMatrix<4, 2, GLfloat>* const values) {
     glProgramUniformMatrix4x2fvEXT(_id, location, count, GL_FALSE, values[0].data());
 }
+#endif
 
 void AbstractShaderProgram::setUniform(const Int location, const UnsignedInt count, const Math::RectangularMatrix<3, 4, Float>* const values) {
     (this->*Context::current()->state().shaderProgram->uniformMatrix3x4fvImplementation)(location, count, values);
@@ -905,6 +941,7 @@ void AbstractShaderProgram::uniformImplementationDefault(const GLint location, c
     glUniformMatrix3x4fv(location, count, GL_FALSE, values[0].data());
 }
 
+#ifndef MAGNUM_TARGET_WEBGL
 void AbstractShaderProgram::uniformImplementationSSO(const GLint location, const GLsizei count, const Math::RectangularMatrix<3, 4, GLfloat>* const values) {
     glProgramUniformMatrix3x4fv(_id, location, count, GL_FALSE, values[0].data());
 }
@@ -912,6 +949,7 @@ void AbstractShaderProgram::uniformImplementationSSO(const GLint location, const
 void AbstractShaderProgram::uniformImplementationDSAEXT_SSOEXT(const GLint location, const GLsizei count, const Math::RectangularMatrix<3, 4, GLfloat>* const values) {
     glProgramUniformMatrix3x4fvEXT(_id, location, count, GL_FALSE, values[0].data());
 }
+#endif
 
 void AbstractShaderProgram::setUniform(const Int location, const UnsignedInt count, const Math::RectangularMatrix<4, 3, Float>* const values) {
     (this->*Context::current()->state().shaderProgram->uniformMatrix4x3fvImplementation)(location, count, values);
@@ -922,6 +960,7 @@ void AbstractShaderProgram::uniformImplementationDefault(const GLint location, c
     glUniformMatrix4x3fv(location, count, GL_FALSE, values[0].data());
 }
 
+#ifndef MAGNUM_TARGET_WEBGL
 void AbstractShaderProgram::uniformImplementationSSO(const GLint location, const GLsizei count, const Math::RectangularMatrix<4, 3, GLfloat>* const values) {
     glProgramUniformMatrix4x3fv(_id, location, count, GL_FALSE, values[0].data());
 }
@@ -930,6 +969,7 @@ void AbstractShaderProgram::uniformImplementationDSAEXT_SSOEXT(const GLint locat
     glProgramUniformMatrix4x3fvEXT(_id, location, count, GL_FALSE, values[0].data());
 }
 #endif
+#endif
 
 #ifndef MAGNUM_TARGET_GLES
 void AbstractShaderProgram::setUniform(const Int location, const UnsignedInt count, const Math::RectangularMatrix<2, 2, Double>* const values) {
diff --git a/src/Magnum/AbstractShaderProgram.h b/src/Magnum/AbstractShaderProgram.h
index c7c3c1c32..f93a93095 100644
--- a/src/Magnum/AbstractShaderProgram.h
+++ b/src/Magnum/AbstractShaderProgram.h
@@ -188,10 +188,16 @@ bindFragmentDataLocationIndexed(NormalOutput, 1, "normal");
     @ref bindAttributeLocation(), @ref bindFragmentDataLocation() or
     @ref bindFragmentDataLocationIndexed().
 @requires_gles30 Explicit location specification of input attributes is not
-    supported in OpenGL ES 2.0, use @ref bindAttributeLocation() instead.
+    supported in OpenGL ES 2.0, use @ref bindAttributeLocation()
+    instead.
 @requires_gles30 Multiple fragment shader outputs are not available in OpenGL
     ES 2.0, similar functionality is available in extension
-    @es_extension{NV,draw_buffers}.
+    @es_extension{EXT,draw_buffers} or @es_extension{NV,draw_buffers}.
+@requires_webgl20 Explicit location specification of input attributes is not
+    supported in WebGL 1.0, use @ref bindAttributeLocation() instead.
+@requires_webgl20 Multiple fragment shader outputs are not available in WebGL
+    1.0, similar functionality is available in extension
+    @webgl_extension{WEBGL,draw_buffers}.
 
 @todo @es_extension{EXT,separate_shader_objects} supports explicit attrib
     location
@@ -229,6 +235,8 @@ Int normalMatrixUniform = uniformLocation("normalMatrix");
     explicit uniform location instead of using @ref uniformLocation().
 @requires_gles31 Explicit uniform location is not supported in OpenGL ES 3.0
     and older. Use @ref uniformLocation() instead.
+@requires_gles Explicit uniform location is not supported in WebGL. Use
+    @ref uniformLocation() instead.
 
 @anchor AbstractShaderProgram-texture-units
 ### Specifying texture binding units
@@ -262,6 +270,8 @@ setUniform(uniformLocation("specularTexture"), 1);
 @requires_gles31 Explicit texture binding unit is not supported in OpenGL ES
     3.0 and older. Use @ref setUniform(Int, const T&) "setUniform(Int, Int)"
     instead.
+@requires_gles Explicit texture binding unit is not supported in WebGL. Use
+    @ref setUniform(Int, const T&) "setUniform(Int, Int)" instead.
 
 @anchor AbstractShaderProgram-transform-feedback
 ### Specifying transform feedback binding points
@@ -307,7 +317,7 @@ setTransformFeedbackOutputs({
     transform feedback output specification instead of using
     @ref setTransformFeedbackOutputs().
 @requires_gl Explicit transform feedback output specification is not available
-    in OpenGL ES.
+    in OpenGL ES or WebGL.
 
 @anchor AbstractShaderProgram-rendering-workflow
 ## Rendering workflow
@@ -353,7 +363,12 @@ also @ref Attribute::DataType enum for additional type options.
     matrix attributes and uniforms (i.e. @ref Matrix2x3, @ref Matrix3x2,
     @ref Matrix2x4, @ref Matrix4x2, @ref Matrix3x4 and @ref Matrix4x3) are not
     available in OpenGL ES 2.0.
-@requires_gl Double attributes and uniforms are not available in OpenGL ES.
+@requires_gl Double attributes and uniforms are not available in OpenGL ES or
+    WebGL.
+@requires_webgl20 Integer attributes, unsigned integer uniforms and non-square
+    matrix attributes and uniforms (i.e. @ref Matrix2x3, @ref Matrix3x2,
+    @ref Matrix2x4, @ref Matrix4x2, @ref Matrix3x4 and @ref Matrix4x3) are not
+    available in WebGL 1.0.
 
 @anchor AbstractShaderProgram-performance-optimization
 ## Performance optimizations
@@ -389,7 +404,8 @@ class MAGNUM_EXPORT AbstractShaderProgram: public AbstractObject {
          * @see @ref setTransformFeedbackOutputs()
          * @requires_gl30 Extension @extension{EXT,transform_feedback}
          * @requires_gles30 Transform feedback is not available in OpenGL ES
-         *      2.0
+         *      2.0.
+         * @requires_webgl20 Transform feedback is not available in WebGL 1.0.
          */
         enum class TransformFeedbackBufferMode: GLenum {
             /** Attributes will be interleaved at one buffer binding point */
@@ -418,7 +434,8 @@ class MAGNUM_EXPORT AbstractShaderProgram: public AbstractObject {
          * OpenGL calls. If neither extension @extension{ARB,shader_atomic_counters}
          * (part of OpenGL 4.2) nor OpenGL ES 3.1 is available, returns `0`.
          * @see @fn_gl{Get} with @def_gl{MAX_ATOMIC_COUNTER_BUFFER_SIZE}
-         * @requires_gles30 Not defined in OpenGL ES 2.0
+         * @requires_gles30 Not defined in OpenGL ES 2.0.
+         * @requires_gles Atomic counters are not available in WebGL.
          */
         static Int maxAtomicCounterBufferSize();
 
@@ -429,7 +446,8 @@ class MAGNUM_EXPORT AbstractShaderProgram: public AbstractObject {
          * OpenGL calls. If neither extension @extension{ARB,compute_shader}
          * (part of OpenGL 4.3) nor OpenGL ES 3.1 is available, returns `0`.
          * @see @fn_gl{Get} with @def_gl{MAX_COMPUTE_SHARED_MEMORY_SIZE}
-         * @requires_gles30 Not defined in OpenGL ES 2.0
+         * @requires_gles30 Not defined in OpenGL ES 2.0.
+         * @requires_gles Compute shaders are not available in WebGL.
          */
         static Int maxComputeSharedMemorySize();
 
@@ -440,7 +458,8 @@ class MAGNUM_EXPORT AbstractShaderProgram: public AbstractObject {
          * OpenGL calls. If neither extension @extension{ARB,compute_shader}
          * (part of OpenGL 4.3) nor OpenGL ES 3.1 is available, returns `0`.
          * @see @fn_gl{Get} with @def_gl{MAX_COMPUTE_WORK_GROUP_INVOCATIONS}
-         * @requires_gles30 Not defined in OpenGL ES 2.0
+         * @requires_gles30 Not defined in OpenGL ES 2.0.
+         * @requires_gles Compute shaders are not available in WebGL.
          */
         static Int maxComputeWorkGroupInvocations();
 
@@ -453,7 +472,8 @@ class MAGNUM_EXPORT AbstractShaderProgram: public AbstractObject {
          * OpenGL calls. If extension @extension{ARB,shader_image_load_store}
          * (part of OpenGL 4.2) or OpenGL ES 3.1 is not available, returns `0`.
          * @see @fn_gl{Get} with @def_gl{MAX_IMAGE_UNITS}
-         * @requires_gles30 Not defined in OpenGL ES 2.0
+         * @requires_gles30 Not defined in OpenGL ES 2.0.
+         * @requires_gles Shader image load/store is not available in WebGL.
          */
         static Int maxImageUnits();
         #endif
@@ -467,12 +487,13 @@ class MAGNUM_EXPORT AbstractShaderProgram: public AbstractObject {
          * (part of OpenGL 4.2) is not available, returns `0`.
          * @see @fn_gl{Get} with @def_gl{MAX_IMAGE_SAMPLES}
          * @requires_gl Multisample image load/store is not available in OpenGL
-         *      ES.
+         *      ES or WebGL.
          */
         static Int maxImageSamples();
         #endif
 
         #ifndef MAGNUM_TARGET_GLES2
+        #ifndef MAGNUM_TARGET_WEBGL
         /**
          * @brief Max supported combined shader output resource count
          *
@@ -481,7 +502,8 @@ class MAGNUM_EXPORT AbstractShaderProgram: public AbstractObject {
          * (part of OpenGL 4.2) nor extension @extension{ARB,shader_storage_buffer_object}
          * (part of OpenGL 4.3) nor OpenGL ES 3.1 is available, returns `0`.
          * @see @fn_gl{Get} with @def_gl{MAX_COMBINED_SHADER_OUTPUT_RESOURCES}
-         * @requires_gles30 Not defined in OpenGL ES 2.0
+         * @requires_gles30 Not defined in OpenGL ES 2.0.
+         * @requires_gles Shader image load/store is not available in WebGL.
          */
         static Int maxCombinedShaderOutputResources();
 
@@ -492,9 +514,11 @@ class MAGNUM_EXPORT AbstractShaderProgram: public AbstractObject {
          * OpenGL calls. If neither extension @extension{ARB,shader_storage_buffer_object}
          * (part of OpenGL 4.3) nor OpenGL ES 3.1 is available, returns `0`.
          * @see @fn_gl{Get} with @def_gl{MAX_SHADER_STORAGE_BLOCK_SIZE}
-         * @requires_gles30 Not defined in OpenGL ES 2.0
+         * @requires_gles30 Not defined in OpenGL ES 2.0.
+         * @requires_gles Shader storage is not available in WebGL.
          */
         static Long maxShaderStorageBlockSize();
+        #endif
 
         /**
          * @brief Max supported uniform block size
@@ -503,10 +527,12 @@ class MAGNUM_EXPORT AbstractShaderProgram: public AbstractObject {
          * OpenGL calls. If extension @extension{ARB,uniform_buffer_object}
          * (part of OpenGL 3.1) is not available, returns `0`.
          * @see @fn_gl{Get} with @def_gl{MAX_UNIFORM_BLOCK_SIZE}
-         * @requires_gles30 Uniform blocks are not available in OpenGL ES 2.0
+         * @requires_gles30 Uniform blocks are not available in OpenGL ES 2.0.
+         * @requires_webgl20 Uniform blocks are not available in WebGL 1.0.
          */
         static Int maxUniformBlockSize();
 
+        #ifndef MAGNUM_TARGET_WEBGL
         /**
          * @brief Max supported explicit uniform location count
          *
@@ -514,9 +540,11 @@ class MAGNUM_EXPORT AbstractShaderProgram: public AbstractObject {
          * OpenGL calls. If neither extension @extension{ARB,explicit_uniform_location}
          * (part of OpenGL 4.3) nor OpenGL ES 3.1 is available, returns `0`.
          * @see @fn_gl{Get} with @def_gl{MAX_UNIFORM_LOCATIONS}
-         * @requires_gles30 Not defined in OpenGL ES 2.0
+         * @requires_gles30 Not defined in OpenGL ES 2.0.
+         * @requires_gles Explicit uniform location is not available in WebGL.
          */
         static Int maxUniformLocations();
+        #endif
 
         /**
          * @brief Min supported program texel offset
@@ -526,7 +554,9 @@ class MAGNUM_EXPORT AbstractShaderProgram: public AbstractObject {
          * OpenGL 3.0) is not available, returns `0`.
          * @see @fn_gl{Get} with @def_gl{MIN_PROGRAM_TEXEL_OFFSET}
          * @requires_gles30 Texture lookup with offset is not available in
-         *      OpenGL ES 2.0
+         *      OpenGL ES 2.0.
+         * @requires_webgl20 Texture lookup with offset is not available in
+         *      WebGL 1.0.
          */
         static Int minTexelOffset();
 
@@ -538,7 +568,9 @@ class MAGNUM_EXPORT AbstractShaderProgram: public AbstractObject {
          * OpenGL 3.0) is not available, returns `0`.
          * @see @fn_gl{Get} with @def_gl{MAX_PROGRAM_TEXEL_OFFSET}
          * @requires_gles30 Texture lookup with offset is not available in
-         *      OpenGL ES 2.0
+         *      OpenGL ES 2.0.
+         * @requires_webgl20 Texture lookup with offset is not available in
+         *      WebGL 1.0.
          */
         static Int maxTexelOffset();
         #endif
@@ -645,7 +677,7 @@ class MAGNUM_EXPORT AbstractShaderProgram: public AbstractObject {
          */
         static bool link(std::initializer_list<std::reference_wrapper<AbstractShaderProgram>> shaders);
 
-        #ifndef MAGNUM_TARGET_GLES2
+        #if !defined(MAGNUM_TARGET_GLES2) && !defined(MAGNUM_TARGET_WEBGL)
         /**
          * @brief Allow retrieving program binary
          *
@@ -653,12 +685,15 @@ class MAGNUM_EXPORT AbstractShaderProgram: public AbstractObject {
          * @see @fn_gl{ProgramParameter} with @def_gl{PROGRAM_BINARY_RETRIEVABLE_HINT}
          * @requires_gl41 Extension @extension{ARB,get_program_binary}
          * @requires_gles30 Always allowed in OpenGL ES 2.0.
+         * @requires_gles Binary program representations are not supported in
+         *      WebGL.
          */
         void setRetrievableBinary(bool enabled) {
             glProgramParameteri(_id, GL_PROGRAM_BINARY_RETRIEVABLE_HINT, enabled ? GL_TRUE : GL_FALSE);
         }
         #endif
 
+        #ifndef MAGNUM_TARGET_WEBGL
         /**
          * @brief Allow the program to be bound to individual pipeline stages
          *
@@ -666,15 +701,16 @@ class MAGNUM_EXPORT AbstractShaderProgram: public AbstractObject {
          * @see @fn_gl{ProgramParameter} with @def_gl{PROGRAM_SEPARABLE}
          * @requires_gl41 Extension @extension{ARB,separate_shader_objects}
          * @requires_es_extension Extension @es_extension{EXT,separate_shader_objects}
+         * @requires_gles Separate shader objects are not supported in WebGL.
          */
         void setSeparable(bool enabled) {
-            /** @todo Remove when extension wrangler is available for ES */
             #ifndef MAGNUM_TARGET_GLES
             glProgramParameteri(_id, GL_PROGRAM_SEPARABLE, enabled ? GL_TRUE : GL_FALSE);
             #else
-            static_cast<void>(enabled);
+            glProgramParameteriEXT(_id, GL_PROGRAM_SEPARABLE_EXT, enabled ? GL_TRUE : GL_FALSE);
             #endif
         }
+        #endif
 
         /**
          * @brief Attach shader
@@ -731,7 +767,7 @@ class MAGNUM_EXPORT AbstractShaderProgram: public AbstractObject {
          *      for more information.
          * @requires_gl33 Extension @extension{ARB,blend_func_extended}
          * @requires_gl Multiple blend function inputs are not available in
-         *      OpenGL ES.
+         *      OpenGL ES or WebGL.
          */
         void bindFragmentDataLocationIndexed(UnsignedInt location, UnsignedInt index, const std::string& name) {
             bindFragmentDataLocationIndexedInternal(location, index, {name.data(), name.size()});
@@ -755,9 +791,10 @@ class MAGNUM_EXPORT AbstractShaderProgram: public AbstractObject {
          *      @ref AbstractShaderProgram-attribute-location "class documentation"
          *      for more information.
          * @requires_gl30 Extension @extension{EXT,gpu_shader4}
-         * @requires_gl Use explicit location specification in OpenGL ES 3.0
-         *      and `gl_FragData[n]` provided by @es_extension2{NV,draw_buffers,GL_NV_draw_buffers}
-         *      in OpenGL ES 2.0.
+         * @requires_gl Use explicit location specification in OpenGL ES 3.0 or
+         *      WebGL 2.0 and `gl_FragData[n]` provided by @es_extension{NV,draw_buffers}
+         *      in OpenGL ES 2.0 and @webgl_extension{WEBGL,draw_buffers} in
+         *      WebGL 1.0.
          */
         void bindFragmentDataLocation(UnsignedInt location, const std::string& name) {
             bindFragmentDataLocationInternal(location, {name.data(), name.size()});
@@ -796,9 +833,10 @@ class MAGNUM_EXPORT AbstractShaderProgram: public AbstractObject {
          *      using `gl_NextBuffer` or `gl_SkipComponents#` names in
          *      @p outputs array
          * @requires_gles30 Transform feedback is not available in OpenGL ES
-         *      2.0
+         *      2.0.
+         * @requires_webgl20 Transform feedback is not available in WebGL 1.0.
          * @requires_gl Special output names `gl_NextBuffer` and
-         *      `gl_SkipComponents#` are not available in OpenGL ES
+         *      `gl_SkipComponents#` are not available in OpenGL ES or WebGL.
          */
         void setTransformFeedbackOutputs(std::initializer_list<std::string> outputs, TransformFeedbackBufferMode bufferMode);
         #endif
@@ -898,6 +936,7 @@ class MAGNUM_EXPORT AbstractShaderProgram: public AbstractObject {
          * @copydoc setUniform(Int, UnsignedInt, const Float*)
          * @requires_gl30 Extension @extension{EXT,gpu_shader4}
          * @requires_gles30 Only signed integers are available in OpenGL ES 2.0.
+         * @requires_webgl20 Only signed integers are available in WebGL 1.0.
          */
         void setUniform(Int location, UnsignedInt count, const UnsignedInt* values);
         void setUniform(Int location, UnsignedInt count, const Math::Vector<2, UnsignedInt>* values); /**< @overload */
@@ -909,7 +948,7 @@ class MAGNUM_EXPORT AbstractShaderProgram: public AbstractObject {
         /**
          * @copydoc setUniform(Int, UnsignedInt, const Float*)
          * @requires_gl40 Extension @extension{ARB,gpu_shader_fp64}
-         * @requires_gl Only floats are available in OpenGL ES.
+         * @requires_gl Only floats are available in OpenGL ES or WebGL.
          */
         void setUniform(Int location, UnsignedInt count, const Double* values);
         void setUniform(Int location, UnsignedInt count, const Math::Vector<2, Double>* values); /**< @overload */
@@ -926,6 +965,7 @@ class MAGNUM_EXPORT AbstractShaderProgram: public AbstractObject {
         /**
          * @copydoc setUniform(Int, UnsignedInt, const Float*)
          * @requires_gles30 Only square matrices are available in OpenGL ES 2.0.
+         * @requires_webgl20 Only square matrices are available in WebGL 1.0.
          */
         void setUniform(Int location, UnsignedInt count, const Math::RectangularMatrix<2, 3, Float>* values);
         void setUniform(Int location, UnsignedInt count, const Math::RectangularMatrix<3, 2, Float>* values); /**< @overload */
@@ -939,7 +979,7 @@ class MAGNUM_EXPORT AbstractShaderProgram: public AbstractObject {
         /**
          * @copydoc setUniform(Int, UnsignedInt, const Float*)
          * @requires_gl40 Extension @extension{ARB,gpu_shader_fp64}
-         * @requires_gl Only floats are available in OpenGL ES.
+         * @requires_gl Only floats are available in OpenGL ES or WebGL.
          */
         void setUniform(Int location, UnsignedInt count, const Math::RectangularMatrix<2, 2, Double>* values);
         void setUniform(Int location, UnsignedInt count, const Math::RectangularMatrix<3, 3, Double>* values); /**< @overload */
@@ -1007,7 +1047,7 @@ class MAGNUM_EXPORT AbstractShaderProgram: public AbstractObject {
         void MAGNUM_LOCAL uniformImplementationDefault(GLint location, GLsizei count, const Math::Vector<3, GLdouble>* values);
         void MAGNUM_LOCAL uniformImplementationDefault(GLint location, GLsizei count, const Math::Vector<4, GLdouble>* values);
         #endif
-        #ifndef MAGNUM_TARGET_GLES2
+        #if !defined(MAGNUM_TARGET_GLES2) && !defined(MAGNUM_TARGET_WEBGL)
         void MAGNUM_LOCAL uniformImplementationSSO(GLint location, GLsizei count, const GLfloat* values);
         void MAGNUM_LOCAL uniformImplementationSSO(GLint location, GLsizei count, const Math::Vector<2, GLfloat>* values);
         void MAGNUM_LOCAL uniformImplementationSSO(GLint location, GLsizei count, const Math::Vector<3, GLfloat>* values);
@@ -1027,6 +1067,7 @@ class MAGNUM_EXPORT AbstractShaderProgram: public AbstractObject {
         void MAGNUM_LOCAL uniformImplementationSSO(GLint location, GLsizei count, const Math::Vector<3, GLdouble>* values);
         void MAGNUM_LOCAL uniformImplementationSSO(GLint location, GLsizei count, const Math::Vector<4, GLdouble>* values);
         #endif
+        #ifndef MAGNUM_TARGET_WEBGL
         void MAGNUM_LOCAL uniformImplementationDSAEXT_SSOEXT(GLint location, GLsizei count, const GLfloat* values);
         void MAGNUM_LOCAL uniformImplementationDSAEXT_SSOEXT(GLint location, GLsizei count, const Math::Vector<2, GLfloat>* values);
         void MAGNUM_LOCAL uniformImplementationDSAEXT_SSOEXT(GLint location, GLsizei count, const Math::Vector<3, GLfloat>* values);
@@ -1041,6 +1082,7 @@ class MAGNUM_EXPORT AbstractShaderProgram: public AbstractObject {
         void MAGNUM_LOCAL uniformImplementationDSAEXT_SSOEXT(GLint location, GLsizei count, const Math::Vector<3, GLuint>* values);
         void MAGNUM_LOCAL uniformImplementationDSAEXT_SSOEXT(GLint location, GLsizei count, const Math::Vector<4, GLuint>* values);
         #endif
+        #endif
         #ifndef MAGNUM_TARGET_GLES
         void MAGNUM_LOCAL uniformImplementationDSAEXT(GLint location, GLsizei count, const GLdouble* values);
         void MAGNUM_LOCAL uniformImplementationDSAEXT(GLint location, GLsizei count, const Math::Vector<2, GLdouble>* values);
@@ -1070,7 +1112,7 @@ class MAGNUM_EXPORT AbstractShaderProgram: public AbstractObject {
         void MAGNUM_LOCAL uniformImplementationDefault(GLint location, GLsizei count, const Math::RectangularMatrix<3, 4, GLdouble>* values);
         void MAGNUM_LOCAL uniformImplementationDefault(GLint location, GLsizei count, const Math::RectangularMatrix<4, 3, GLdouble>* values);
         #endif
-        #ifndef MAGNUM_TARGET_GLES2
+        #if !defined(MAGNUM_TARGET_GLES2) && !defined(MAGNUM_TARGET_WEBGL)
         void MAGNUM_LOCAL uniformImplementationSSO(GLint location, GLsizei count, const Math::RectangularMatrix<2, 2, GLfloat>* values);
         void MAGNUM_LOCAL uniformImplementationSSO(GLint location, GLsizei count, const Math::RectangularMatrix<3, 3, GLfloat>* values);
         void MAGNUM_LOCAL uniformImplementationSSO(GLint location, GLsizei count, const Math::RectangularMatrix<4, 4, GLfloat>* values);
@@ -1092,6 +1134,7 @@ class MAGNUM_EXPORT AbstractShaderProgram: public AbstractObject {
         void MAGNUM_LOCAL uniformImplementationSSO(GLint location, GLsizei count, const Math::RectangularMatrix<3, 4, GLdouble>* values);
         void MAGNUM_LOCAL uniformImplementationSSO(GLint location, GLsizei count, const Math::RectangularMatrix<4, 3, GLdouble>* values);
         #endif
+        #ifndef MAGNUM_TARGET_WEBGL
         void MAGNUM_LOCAL uniformImplementationDSAEXT_SSOEXT(GLint location, GLsizei count, const Math::RectangularMatrix<2, 2, GLfloat>* values);
         void MAGNUM_LOCAL uniformImplementationDSAEXT_SSOEXT(GLint location, GLsizei count, const Math::RectangularMatrix<3, 3, GLfloat>* values);
         void MAGNUM_LOCAL uniformImplementationDSAEXT_SSOEXT(GLint location, GLsizei count, const Math::RectangularMatrix<4, 4, GLfloat>* values);
@@ -1103,6 +1146,7 @@ class MAGNUM_EXPORT AbstractShaderProgram: public AbstractObject {
         void MAGNUM_LOCAL uniformImplementationDSAEXT_SSOEXT(GLint location, GLsizei count, const Math::RectangularMatrix<3, 4, GLfloat>* values);
         void MAGNUM_LOCAL uniformImplementationDSAEXT_SSOEXT(GLint location, GLsizei count, const Math::RectangularMatrix<4, 3, GLfloat>* values);
         #endif
+        #endif
         #ifndef MAGNUM_TARGET_GLES
         void MAGNUM_LOCAL uniformImplementationDSAEXT(GLint location, GLsizei count, const Math::RectangularMatrix<2, 2, GLdouble>* values);
         void MAGNUM_LOCAL uniformImplementationDSAEXT(GLint location, GLsizei count, const Math::RectangularMatrix<3, 3, GLdouble>* values);
diff --git a/src/Magnum/Attribute.h b/src/Magnum/Attribute.h
index 99428d1fc..2faa39b74 100644
--- a/src/Magnum/Attribute.h
+++ b/src/Magnum/Attribute.h
@@ -138,7 +138,7 @@ template<UnsignedInt location, class T> class Attribute {
              * and @ref DataOption::Normalized.
              * @requires_gl32 Extension @extension{ARB,vertex_array_bgra}
              * @requires_gl Only RGBA component ordering is supported in OpenGL
-             *      ES.
+             *      ES and WebGL.
              */
             BGRA = GL_BGRA
             #endif
@@ -162,13 +162,17 @@ template<UnsignedInt location, class T> class Attribute {
             UnsignedInt = GL_UNSIGNED_INT,      /**< Unsigned int */
             Int = GL_INT,                       /**< Int */
 
+            #ifndef MAGNUM_TARGET_WEBGL
             /**
              * Half float. Only for float attribute types.
              * @requires_gl30 Extension @extension{ARB,half_float_vertex}
              * @requires_gles30 Extension @es_extension{OES,vertex_half_float}
              *      in OpenGL ES 2.0
+             * @requires_webgl20 Half float vertex attributes are not available
+             *      in WebGL 1.0.
              */
             HalfFloat = GL_HALF_FLOAT,
+            #endif
 
             /** Float. Only for float attribute types. */
             Float = GL_FLOAT,
@@ -176,7 +180,7 @@ template<UnsignedInt location, class T> class Attribute {
             #ifndef MAGNUM_TARGET_GLES
             /**
              * Double. Only for float and double attribute types.
-             * @requires_gl Only floats are available in OpenGL ES.
+             * @requires_gl Only floats are available in OpenGL ES or WebGL.
              */
             Double = GL_DOUBLE,
 
@@ -185,7 +189,7 @@ template<UnsignedInt location, class T> class Attribute {
              * vector attribute type.
              * @requires_gl44 Extension @extension{ARB,vertex_type_10f_11f_11f_rev}
              * @requires_gl Packed float attributes are not available in OpenGL
-             *      ES.
+             *      ES or WebGL.
              */
             UnsignedInt10f11f11fRev = GL_UNSIGNED_INT_10F_11F_11F_REV,
             #endif
@@ -199,7 +203,9 @@ template<UnsignedInt location, class T> class Attribute {
              * @todo How about (incompatible) @es_extension{OES,vertex_type_10_10_10_2}?
              * @requires_gl33 Extension @extension{ARB,vertex_type_2_10_10_10_rev}
              * @requires_gles30 Packed attributes are not available in OpenGL
-             *      ES 2.0
+             *      ES 2.0.
+             * @requires_webgl20 Packed attributes are not available in WebGL
+             *      1.0.
              */
             UnsignedInt2101010Rev = GL_UNSIGNED_INT_2_10_10_10_REV,
 
@@ -208,7 +214,9 @@ template<UnsignedInt location, class T> class Attribute {
              * vector attribute type.
              * @requires_gl33 Extension @extension{ARB,vertex_type_2_10_10_10_rev}
              * @requires_gles30 Packed attributes are not available in OpenGL
-             *      ES 2.0
+             *      ES 2.0.
+             * @requires_webgl20 Packed attributes are not available in WebGL
+             *      1.0.
              */
             Int2101010Rev = GL_INT_2_10_10_10_REV
             #endif
diff --git a/src/Magnum/Implementation/ShaderProgramState.cpp b/src/Magnum/Implementation/ShaderProgramState.cpp
index b3fc06e4d..1508b40cd 100644
--- a/src/Magnum/Implementation/ShaderProgramState.cpp
+++ b/src/Magnum/Implementation/ShaderProgramState.cpp
@@ -35,13 +35,19 @@ namespace Magnum { namespace Implementation {
 
 ShaderProgramState::ShaderProgramState(Context& context, std::vector<std::string>& extensions): current(0), maxVertexAttributes(0)
         #ifndef MAGNUM_TARGET_GLES2
-        , maxAtomicCounterBufferSize(0), maxComputeSharedMemorySize(0), maxComputeWorkGroupInvocations(0), maxImageUnits(0), maxCombinedShaderOutputResources(0), maxUniformLocations(0), minTexelOffset(0), maxTexelOffset(0), maxUniformBlockSize(0), maxShaderStorageBlockSize(0)
+        #ifndef MAGNUM_TARGET_WEBGL
+        , maxAtomicCounterBufferSize(0), maxComputeSharedMemorySize(0), maxComputeWorkGroupInvocations(0), maxImageUnits(0), maxCombinedShaderOutputResources(0), maxUniformLocations(0)
+        #endif
+        , minTexelOffset(0), maxTexelOffset(0), maxUniformBlockSize(0)
+        #ifndef MAGNUM_TARGET_WEBGL
+        , maxShaderStorageBlockSize(0)
+        #endif
         #endif
         #ifndef MAGNUM_TARGET_GLES
         , maxImageSamples(0)
         #endif
 {
-    #ifndef MAGNUM_TARGET_GLES2
+    #if !defined(MAGNUM_TARGET_GLES2) && !defined(MAGNUM_TARGET_WEBGL)
     #ifndef MAGNUM_TARGET_GLES
     if(context.isExtensionSupported<Extensions::GL::ARB::separate_shader_objects>())
     #else
@@ -94,6 +100,7 @@ ShaderProgramState::ShaderProgramState(Context& context, std::vector<std::string
     } else
     #endif
 
+    #ifndef MAGNUM_TARGET_WEBGL
     #ifndef MAGNUM_TARGET_GLES
     if(context.isExtensionSupported<Extensions::GL::EXT::direct_state_access>())
     #else
@@ -149,7 +156,9 @@ ShaderProgramState::ShaderProgramState(Context& context, std::vector<std::string
         uniformMatrix3x4dvImplementation = &AbstractShaderProgram::uniformImplementationDSAEXT;
         uniformMatrix4x3dvImplementation = &AbstractShaderProgram::uniformImplementationDSAEXT;
         #endif
-    } else {
+    } else
+    #endif
+    {
         uniform1fvImplementation = &AbstractShaderProgram::uniformImplementationDefault;
         uniform2fvImplementation = &AbstractShaderProgram::uniformImplementationDefault;
         uniform3fvImplementation = &AbstractShaderProgram::uniformImplementationDefault;
@@ -194,6 +203,11 @@ ShaderProgramState::ShaderProgramState(Context& context, std::vector<std::string
         uniformMatrix4x3dvImplementation = &AbstractShaderProgram::uniformImplementationDefault;
         #endif
     }
+
+    #ifdef MAGNUM_TARGET_WEBGL
+    static_cast<void>(context);
+    static_cast<void>(extensions);
+    #endif
 }
 
 void ShaderProgramState::reset() {
diff --git a/src/Magnum/Implementation/ShaderProgramState.h b/src/Magnum/Implementation/ShaderProgramState.h
index b30c8c2be..d972729d4 100644
--- a/src/Magnum/Implementation/ShaderProgramState.h
+++ b/src/Magnum/Implementation/ShaderProgramState.h
@@ -87,17 +87,21 @@ struct ShaderProgramState {
 
     GLint maxVertexAttributes;
     #ifndef MAGNUM_TARGET_GLES2
+    #ifndef MAGNUM_TARGET_WEBGL
     GLint maxAtomicCounterBufferSize,
         maxComputeSharedMemorySize,
         maxComputeWorkGroupInvocations,
         maxImageUnits,
         maxCombinedShaderOutputResources,
-        maxUniformLocations,
-        minTexelOffset,
+        maxUniformLocations;
+    #endif
+    GLint minTexelOffset,
         maxTexelOffset,
         maxUniformBlockSize;
+    #ifndef MAGNUM_TARGET_WEBGL
     GLint64 maxShaderStorageBlockSize;
     #endif
+    #endif
 
     #ifndef MAGNUM_TARGET_GLES
     GLint maxImageSamples;
diff --git a/src/Magnum/Implementation/ShaderState.h b/src/Magnum/Implementation/ShaderState.h
index 6c6f678b0..b1afd9619 100644
--- a/src/Magnum/Implementation/ShaderState.h
+++ b/src/Magnum/Implementation/ShaderState.h
@@ -37,7 +37,7 @@ struct ShaderState {
         #ifndef MAGNUM_TARGET_GLES
         maxTessellationControlInputComponents{}, maxTessellationControlOutputComponents{}, maxTessellationControlTotalOutputComponents{}, maxTessellationEvaluationInputComponents{}, maxTessellationEvaluationOutputComponents{}, maxGeometryInputComponents{}, maxGeometryOutputComponents{}, maxGeometryTotalOutputComponents{},
         #endif
-        #ifndef MAGNUM_TARGET_GLES2
+        #if !defined(MAGNUM_TARGET_GLES2) && !defined(MAGNUM_TARGET_WEBGL)
         maxAtomicCounterBuffers{}, maxCombinedAtomicCounterBuffers{}, maxAtomicCounters{}, maxCombinedAtomicCounters{}, maxImageUniforms{}, maxCombinedImageUniforms{}, maxShaderStorageBlocks{}, maxCombinedShaderStorageBlocks{},
         #endif
         maxTextureImageUnits{}, maxTextureImageUnitsCombined{},
@@ -70,7 +70,7 @@ struct ShaderState {
         maxGeometryOutputComponents,
         maxGeometryTotalOutputComponents;
     #endif
-    #ifndef MAGNUM_TARGET_GLES2
+    #if !defined(MAGNUM_TARGET_GLES2) && !defined(MAGNUM_TARGET_WEBGL)
     GLint maxAtomicCounterBuffers[StageCount];
     GLint maxCombinedAtomicCounterBuffers;
     GLint maxAtomicCounters[StageCount];
diff --git a/src/Magnum/Shader.cpp b/src/Magnum/Shader.cpp
index 789459494..bd2a69b7e 100644
--- a/src/Magnum/Shader.cpp
+++ b/src/Magnum/Shader.cpp
@@ -59,7 +59,7 @@ std::string shaderName(const Shader::Type type) {
         case Shader::Type::TessellationControl:     return "tessellation control";
         case Shader::Type::TessellationEvaluation:  return "tessellation evaluation";
         #endif
-        #ifndef MAGNUM_TARGET_GLES2
+        #if !defined(MAGNUM_TARGET_GLES2) && !defined(MAGNUM_TARGET_WEBGL)
         case Shader::Type::Compute:                 return "compute";
         #endif
         case Shader::Type::Fragment:                return "fragment";
@@ -72,7 +72,7 @@ UnsignedInt typeToIndex(const Shader::Type type) {
     switch(type) {
         case Shader::Type::Vertex:                  return 0;
         case Shader::Type::Fragment:                return 1;
-        #ifndef MAGNUM_TARGET_GLES2
+        #if !defined(MAGNUM_TARGET_GLES2) && !defined(MAGNUM_TARGET_WEBGL)
         case Shader::Type::Compute:                 return 2;
         #endif
         #ifndef MAGNUM_TARGET_GLES
@@ -254,7 +254,7 @@ Int Shader::maxFragmentInputComponents() {
     return value;
 }
 
-#ifndef MAGNUM_TARGET_GLES2
+#if !defined(MAGNUM_TARGET_GLES2) && !defined(MAGNUM_TARGET_WEBGL)
 Int Shader::maxAtomicCounterBuffers(const Type type) {
     if(
         #ifndef MAGNUM_TARGET_GLES
@@ -471,7 +471,7 @@ Int Shader::maxTextureImageUnits(const Type type) {
     constexpr static GLenum what[] = {
         GL_MAX_VERTEX_TEXTURE_IMAGE_UNITS,
         GL_MAX_TEXTURE_IMAGE_UNITS,
-        #ifndef MAGNUM_TARGET_GLES2
+        #if !defined(MAGNUM_TARGET_GLES2) && !defined(MAGNUM_TARGET_WEBGL)
         GL_MAX_COMPUTE_TEXTURE_IMAGE_UNITS,
         #endif
         #ifndef MAGNUM_TARGET_GLES
@@ -512,7 +512,7 @@ Int Shader::maxUniformBlocks(const Type type) {
     constexpr static GLenum what[] = {
         GL_MAX_VERTEX_UNIFORM_BLOCKS,
         GL_MAX_FRAGMENT_UNIFORM_BLOCKS,
-        #ifndef MAGNUM_TARGET_GLES2
+        #ifndef MAGNUM_TARGET_WEBGL
         GL_MAX_COMPUTE_UNIFORM_BLOCKS,
         #endif
         #ifndef MAGNUM_TARGET_GLES
@@ -555,7 +555,9 @@ Int Shader::maxUniformComponents(const Type type) {
     constexpr static GLenum what[] = {
         GL_MAX_VERTEX_UNIFORM_COMPONENTS,
         GL_MAX_FRAGMENT_UNIFORM_COMPONENTS,
+        #ifndef MAGNUM_TARGET_WEBGL
         GL_MAX_COMPUTE_UNIFORM_COMPONENTS,
+        #endif
         #ifndef MAGNUM_TARGET_GLES
         GL_MAX_GEOMETRY_UNIFORM_COMPONENTS,
         GL_MAX_TESS_CONTROL_UNIFORM_COMPONENTS,
@@ -596,7 +598,7 @@ Int Shader::maxCombinedUniformComponents(const Type type) {
     constexpr static GLenum what[] = {
         GL_MAX_COMBINED_VERTEX_UNIFORM_COMPONENTS,
         GL_MAX_COMBINED_FRAGMENT_UNIFORM_COMPONENTS,
-        #ifndef MAGNUM_TARGET_GLES2
+        #ifndef MAGNUM_TARGET_WEBGL
         GL_MAX_COMBINED_COMPUTE_UNIFORM_COMPONENTS,
         #endif
         #ifndef MAGNUM_TARGET_GLES
@@ -631,8 +633,10 @@ Shader::Shader(const Version version, const Type type): _type(type), _id(0) {
         #else
         case Version::GLES200: _sources.push_back("#version 100\n"); return;
         case Version::GLES300: _sources.push_back("#version 300 es\n"); return;
+        #ifndef MAGNUM_TARGET_WEBGL
         case Version::GLES310: _sources.push_back("#version 310 es\n"); return;
         #endif
+        #endif
 
         /* The user is responsible for (not) adding #version directive */
         case Version::None: return;
@@ -799,7 +803,7 @@ Debug operator<<(Debug debug, const Shader::Type value) {
         _c(TessellationEvaluation)
         _c(Geometry)
         #endif
-        #ifndef MAGNUM_TARGET_GLES2
+        #if !defined(MAGNUM_TARGET_GLES2) && !defined(MAGNUM_TARGET_WEBGL)
         _c(Compute)
         #endif
         _c(Fragment)
diff --git a/src/Magnum/Shader.h b/src/Magnum/Shader.h
index 26c3a1be5..b572b4bcd 100644
--- a/src/Magnum/Shader.h
+++ b/src/Magnum/Shader.h
@@ -71,31 +71,35 @@ class MAGNUM_EXPORT Shader: public AbstractObject {
             /**
              * Tessellation control shader
              * @requires_gl40 Extension @extension{ARB,tessellation_shader}
-             * @requires_gl Tessellation shaders are not available in OpenGL ES.
+             * @requires_gl Tessellation shaders are not available in OpenGL ES
+             *      or WebGL.
              */
             TessellationControl = GL_TESS_CONTROL_SHADER,
 
             /**
              * Tessellation evaluation shader
              * @requires_gl40 Extension @extension{ARB,tessellation_shader}
-             * @requires_gl Tessellation shaders are not available in OpenGL ES.
+             * @requires_gl Tessellation shaders are not available in OpenGL ES
+             *      or WebGL.
              */
             TessellationEvaluation = GL_TESS_EVALUATION_SHADER,
 
             /**
              * Geometry shader
              * @requires_gl32 Extension @extension{ARB,geometry_shader4}
-             * @requires_gl Geometry shaders are not available in OpenGL ES.
+             * @requires_gl Geometry shaders are not available in OpenGL ES or
+             *      WebGL.
              */
             Geometry = GL_GEOMETRY_SHADER,
             #endif
 
-            #ifndef MAGNUM_TARGET_GLES2
+            #if !defined(MAGNUM_TARGET_GLES2) && !defined(MAGNUM_TARGET_WEBGL)
             /**
              * Compute shader
              * @requires_gl43 Extension @extension{ARB,compute_shader}
              * @requires_gles31 Compute shaders are not available in OpenGL ES
-             *      3.0 and older
+             *      3.0 and older.
+             * @requires_gles Compute shaders are not available in WebGL.
              */
             Compute = GL_COMPUTE_SHADER,
             #endif
@@ -125,7 +129,8 @@ class MAGNUM_EXPORT Shader: public AbstractObject {
          * OpenGL calls. If extension @extension{ARB,tessellation_shader} (part
          * of OpenGL 4.0) is not available, returns `0`.
          * @see @fn_gl{Get} with @def_gl{MAX_TESS_CONTROL_INPUT_COMPONENTS}
-         * @requires_gl Tessellation shaders are not available in OpenGL ES.
+         * @requires_gl Tessellation shaders are not available in OpenGL ES or
+         *      WebGL.
          */
         static Int maxTessellationControlInputComponents();
 
@@ -136,7 +141,8 @@ class MAGNUM_EXPORT Shader: public AbstractObject {
          * OpenGL calls. If extension @extension{ARB,tessellation_shader} (part
          * of OpenGL 4.0) is not available, returns `0`.
          * @see @fn_gl{Get} with @def_gl{MAX_TESS_CONTROL_OUTPUT_COMPONENTS}
-         * @requires_gl Tessellation shaders are not available in OpenGL ES.
+         * @requires_gl Tessellation shaders are not available in OpenGL ES or
+         *      WebGL.
          */
         static Int maxTessellationControlOutputComponents();
 
@@ -147,7 +153,8 @@ class MAGNUM_EXPORT Shader: public AbstractObject {
          * OpenGL calls. If extension @extension{ARB,tessellation_shader} (part
          * of OpenGL 4.0) is not available, returns `0`.
          * @see @fn_gl{Get} with @def_gl{MAX_TESS_CONTROL_TOTAL_OUTPUT_COMPONENTS}
-         * @requires_gl Tessellation shaders are not available in OpenGL ES.
+         * @requires_gl Tessellation shaders are not available in OpenGL ES or
+         *      WebGL.
          */
         static Int maxTessellationControlTotalOutputComponents();
 
@@ -158,7 +165,8 @@ class MAGNUM_EXPORT Shader: public AbstractObject {
          * OpenGL calls. If extension @extension{ARB,tessellation_shader} (part
          * of OpenGL 4.0) is not available, returns `0`.
          * @see @fn_gl{Get} with @def_gl{MAX_TESS_EVALUATION_INPUT_COMPONENTS}
-         * @requires_gl Tessellation shaders are not available in OpenGL ES.
+         * @requires_gl Tessellation shaders are not available in OpenGL ES or
+         *      WebGL.
          */
         static Int maxTessellationEvaluationInputComponents();
 
@@ -169,7 +177,8 @@ class MAGNUM_EXPORT Shader: public AbstractObject {
          * OpenGL calls. If extension @extension{ARB,tessellation_shader} (part
          * of OpenGL 4.0) is not available, returns `0`.
          * @see @fn_gl{Get} with @def_gl{MAX_TESS_EVALUATION_OUTPUT_COMPONENTS}
-         * @requires_gl Tessellation shaders are not available in OpenGL ES.
+         * @requires_gl Tessellation shaders are not available in OpenGL ES or
+         *      WebGL.
          */
         static Int maxTessellationEvaluationOutputComponents();
 
@@ -180,7 +189,8 @@ class MAGNUM_EXPORT Shader: public AbstractObject {
          * OpenGL calls. If extension @extension{ARB,geometry_shader4} (part of
          * OpenGL 3.2) is not available, returns `0`.
          * @see @fn_gl{Get} with @def_gl{MAX_GEOMETRY_INPUT_COMPONENTS}
-         * @requires_gl Geometry shaders are not available in OpenGL ES.
+         * @requires_gl Geometry shaders are not available in OpenGL ES or
+         *      WebGL.
          */
         static Int maxGeometryInputComponents();
 
@@ -191,7 +201,8 @@ class MAGNUM_EXPORT Shader: public AbstractObject {
          * OpenGL calls. If extension @extension{ARB,geometry_shader4} (part of
          * OpenGL 3.2) is not available, returns `0`.
          * @see @fn_gl{Get} with @def_gl{MAX_GEOMETRY_OUTPUT_COMPONENTS}
-         * @requires_gl Geometry shaders are not available in OpenGL ES.
+         * @requires_gl Geometry shaders are not available in OpenGL ES or
+         *      WebGL.
          */
         static Int maxGeometryOutputComponents();
 
@@ -202,7 +213,8 @@ class MAGNUM_EXPORT Shader: public AbstractObject {
          * OpenGL calls. If extension @extension{ARB,geometry_shader4} (part of
          * OpenGL 3.2) is not available, returns `0`.
          * @see @fn_gl{Get} with @def_gl{MAX_GEOMETRY_TOTAL_OUTPUT_COMPONENTS}
-         * @requires_gl Geometry shaders are not available in OpenGL ES.
+         * @requires_gl Geometry shaders are not available in OpenGL ES or
+         *      WebGL.
          */
         static Int maxGeometryTotalOutputComponents();
         #endif
@@ -238,7 +250,7 @@ class MAGNUM_EXPORT Shader: public AbstractObject {
          */
         static Int maxUniformComponents(Type type);
 
-        #ifndef MAGNUM_TARGET_GLES2
+        #if !defined(MAGNUM_TARGET_GLES2) && !defined(MAGNUM_TARGET_WEBGL)
         /**
          * @brief Max supported atomic counter buffer count
          *
@@ -253,7 +265,8 @@ class MAGNUM_EXPORT Shader: public AbstractObject {
          *      @def_gl{MAX_GEOMETRY_ATOMIC_COUNTER_BUFFERS},
          *      @def_gl{MAX_COMPUTE_ATOMIC_COUNTER_BUFFERS} or
          *      @def_gl{MAX_FRAGMENT_ATOMIC_COUNTER_BUFFERS}
-         * @requires_gles30 Not defined in OpenGL ES 2.0
+         * @requires_gles30 Not defined in OpenGL ES 2.0.
+         * @requires_gles Atomic counters are not available in WebGL.
          */
         static Int maxAtomicCounterBuffers(Type type);
 
@@ -265,7 +278,8 @@ class MAGNUM_EXPORT Shader: public AbstractObject {
          * (part of OpenGL 4.2) nor OpenGL ES 3.1 is available, returns `0`.
          * @see @ref maxAtomicCounterBuffers(), @ref maxCombinedAtomicCounters(),
          *      @fn_gl{Get} with @def_gl{MAX_COMBINED_ATOMIC_COUNTER_BUFFERS}
-         * @requires_gles30 Not defined in OpenGL ES 2.0
+         * @requires_gles30 Not defined in OpenGL ES 2.0.
+         * @requires_gles Atomic counters are not available in WebGL.
          */
         static Int maxCombinedAtomicCounterBuffers();
 
@@ -283,7 +297,8 @@ class MAGNUM_EXPORT Shader: public AbstractObject {
          *      @def_gl{MAX_GEOMETRY_ATOMIC_COUNTERS},
          *      @def_gl{MAX_COMPUTE_ATOMIC_COUNTERS} or
          *      @def_gl{MAX_FRAGMENT_ATOMIC_COUNTERS}
-         * @requires_gles30 Not defined in OpenGL ES 2.0
+         * @requires_gles30 Not defined in OpenGL ES 2.0.
+         * @requires_gles Atomic counters are not available in WebGL.
          */
         static Int maxAtomicCounters(Type type);
 
@@ -295,7 +310,8 @@ class MAGNUM_EXPORT Shader: public AbstractObject {
          * (part of OpenGL 4.2) nor OpenGL ES 3.1 is available, returns `0`.
          * @see @ref maxAtomicCounters(), @ref maxCombinedAtomicCounterBuffers(),
          *      @fn_gl{Get} with @def_gl{MAX_COMBINED_ATOMIC_COUNTERS}
-         * @requires_gles30 Not defined in OpenGL ES 2.0
+         * @requires_gles30 Not defined in OpenGL ES 2.0.
+         * @requires_gles Atomic counters are not available in WebGL.
          */
         static Int maxCombinedAtomicCounters();
 
@@ -313,7 +329,8 @@ class MAGNUM_EXPORT Shader: public AbstractObject {
          *      @def_gl{MAX_GEOMETRY_IMAGE_UNIFORMS},
          *      @def_gl{MAX_COMPUTE_IMAGE_UNIFORMS} or
          *      @def_gl{MAX_FRAGMENT_IMAGE_UNIFORMS}
-         * @requires_gles30 Not defined in OpenGL ES 2.0
+         * @requires_gles30 Not defined in OpenGL ES 2.0.
+         * @requires_gles Shader image load/store is not available in WebGL.
          */
         static Int maxImageUniforms(Type type);
 
@@ -325,7 +342,8 @@ class MAGNUM_EXPORT Shader: public AbstractObject {
          * (part of OpenGL 4.2) nor OpenGL ES 3.1 is available, returns `0`.
          * @see @ref maxImageUniforms(),
          *      @fn_gl{Get} with @def_gl{MAX_COMBINED_IMAGE_UNIFORMS}
-         * @requires_gles30 Not defined in OpenGL ES 2.0
+         * @requires_gles30 Not defined in OpenGL ES 2.0.
+         * @requires_gles Shader image load/store is not available in WebGL.
          */
         static Int maxCombinedImageUniforms();
 
@@ -343,7 +361,8 @@ class MAGNUM_EXPORT Shader: public AbstractObject {
          *      @def_gl{MAX_GEOMETRY_SHADER_STORAGE_BLOCKS},
          *      @def_gl{MAX_COMPUTE_SHADER_STORAGE_BLOCKS} or
          *      @def_gl{MAX_FRAGMENT_SHADER_STORAGE_BLOCKS}
-         * @requires_gles30 Not defined in OpenGL ES 2.0
+         * @requires_gles30 Not defined in OpenGL ES 2.0.
+         * @requires_gles Shader image load/store is not available in WebGL.
          */
         static Int maxShaderStorageBlocks(Type type);
 
@@ -355,7 +374,8 @@ class MAGNUM_EXPORT Shader: public AbstractObject {
          * (part of OpenGL 4.3) nor OpenGL ES 3.1 is available, returns `0`.
          * @see @ref maxShaderStorageBlocks(),
          *      @fn_gl{Get} with @def_gl{MAX_COMBINED_SHADER_STORAGE_BLOCKS}
-         * @requires_gles30 Not defined in OpenGL ES 2.0
+         * @requires_gles30 Not defined in OpenGL ES 2.0.
+         * @requires_gles Shader storage is not available in WebGL.
          */
         static Int maxCombinedShaderStorageBlocks();
         #endif
@@ -403,6 +423,7 @@ class MAGNUM_EXPORT Shader: public AbstractObject {
          *      @def_gl{MAX_COMPUTE_UNIFORM_BLOCKS} or
          *      @def_gl{MAX_FRAGMENT_UNIFORM_BLOCKS}
          * @requires_gles30 Uniform blocks are not available in OpenGL ES 2.0.
+         * @requires_webgl20 Uniform blocks are not available in WebGL 1.0.
          */
         static Int maxUniformBlocks(Type type);
 
@@ -416,6 +437,7 @@ class MAGNUM_EXPORT Shader: public AbstractObject {
          *      @ref maxCombinedUniformComponents(),
          *      @fn_gl{Get} with @def_gl{MAX_COMBINED_UNIFORM_BLOCKS}
          * @requires_gles30 Uniform blocks are not available in OpenGL ES 2.0.
+         * @requires_webgl20 Uniform blocks are not available in WebGL 1.0.
          */
         static Int maxCombinedUniformBlocks();
 
@@ -434,6 +456,7 @@ class MAGNUM_EXPORT Shader: public AbstractObject {
          *      @def_gl{MAX_COMBINED_COMPUTE_UNIFORM_COMPONENTS} or
          *      @def_gl{MAX_COMBINED_FRAGMENT_UNIFORM_COMPONENTS}
          * @requires_gles30 Uniform blocks are not available in OpenGL ES 2.0.
+         * @requires_webgl20 Uniform blocks are not available in WebGL 1.0.
          */
         static Int maxCombinedUniformComponents(Type type);
         #endif