diff --git a/src/Text/Renderer.cpp b/src/Text/Renderer.cpp
index adc103cfc..534e3e26f 100644
--- a/src/Text/Renderer.cpp
+++ b/src/Text/Renderer.cpp
@@ -357,6 +357,7 @@ void AbstractRenderer::reserve(const uint32_t glyphCount, const BufferUsage vert
     /* Prefill index buffer */
     unsigned char* const indices = static_cast<unsigned char*>(bufferMapImplementation(_indexBuffer, indexData.size()));
     CORRADE_INTERNAL_ASSERT(indices);
+    /** @todo Emscripten: it can be done without this copying altogether */
     std::copy(indexData.begin(), indexData.end(), indices);
     bufferUnmapImplementation(_indexBuffer);
 }