diff --git a/doc/changelog.dox b/doc/changelog.dox
index 4632bd783..13c7e5c19 100644
--- a/doc/changelog.dox
+++ b/doc/changelog.dox
@@ -185,6 +185,12 @@ See also:
     allocation function, which changed signature in 2.0.5 and caused runtime
     failures when `-s ASSERTIONS` was enabled. A public stable API is now used
     instead, see [mosra/magnum#483](https://github.com/mosra/magnum/pull/483).
+-   Because hardcoding canvas size using
+    @ref Platform::EmscriptenApplication::Configuration::setSize() "Platform::Application::Configuration::setSize()"
+    on WebGL is usually a wrong thing to do, both
+    @ref Platform::EmscriptenApplication and @ref Platform::Sdl2Application now
+    notify about that in the verbose output (enabled with `?magnum-log=verbose`),
+    previously only autodetected canvas size got printed
 
 @subsubsection changelog-latest-changes-shaders Shaders library
 
diff --git a/src/Magnum/Platform/EmscriptenApplication.cpp b/src/Magnum/Platform/EmscriptenApplication.cpp
index e6c3e940b..526762f7c 100644
--- a/src/Magnum/Platform/EmscriptenApplication.cpp
+++ b/src/Magnum/Platform/EmscriptenApplication.cpp
@@ -404,6 +404,9 @@ bool EmscriptenApplication::tryCreate(const Configuration& configuration, const
     Vector2i canvasSize;
     if(!configuration.size().isZero()) {
         canvasSize = configuration.size();
+        /* Because hardcoding canvas size for WebGL is usually a wrong thing to
+           do, notify about that in the verbose output */
+        Debug{verbose} << "Platform::EmscriptenApplication::tryCreate(): hardcoded canvas size" << canvasSize;
     } else {
         canvasSize = _lastKnownCanvasSize;
         Debug{verbose} << "Platform::EmscriptenApplication::tryCreate(): autodetected canvas size" << canvasSize;
diff --git a/src/Magnum/Platform/Sdl2Application.cpp b/src/Magnum/Platform/Sdl2Application.cpp
index b186c0d36..d61a0496f 100644
--- a/src/Magnum/Platform/Sdl2Application.cpp
+++ b/src/Magnum/Platform/Sdl2Application.cpp
@@ -408,6 +408,9 @@ bool Sdl2Application::tryCreate(const Configuration& configuration) {
     Vector2i windowSize;
     if(!configuration.size().isZero()) {
         windowSize = configuration.size();
+        /* Because hardcoding canvas size for WebGL is usually a wrong thing to
+           do, notify about that in the verbose output */
+        Debug{_verboseLog ? Debug::output() : nullptr} << "Platform::Sdl2Application::tryCreate(): hardcoded canvas size" << windowSize;
     } else {
         windowSize = _lastKnownCanvasSize;
         Debug{_verboseLog ? Debug::output() : nullptr} << "Platform::Sdl2Application::tryCreate(): autodetected canvas size" << windowSize;
@@ -636,6 +639,9 @@ bool Sdl2Application::tryCreate(const Configuration& configuration, const GLConf
     Vector2i windowSize;
     if(!configuration.size().isZero()) {
         windowSize = configuration.size();
+        /* Because hardcoding canvas size for WebGL is usually a wrong thing to
+           do, notify about that in the verbose output */
+        Debug{_verboseLog ? Debug::output() : nullptr} << "Platform::Sdl2Application::tryCreate(): hardcoded canvas size" << windowSize;
     } else {
         windowSize = _lastKnownCanvasSize;
         Debug{_verboseLog ? Debug::output() : nullptr} << "Platform::Sdl2Application::tryCreate(): autodetected canvas size" << windowSize;