The first run failed because of the syntax:

#if EMSCRIPTEN_USE_PORT_CONTRIB_GLFW3 >= 3'4'0'20240817

../../backends/imgui_impl_glfw.cpp:649:43: error: token is not a valid binary operator in a preprocessor subexpression
#if EMSCRIPTEN_USE_PORT_CONTRIB_GLFW3 >= 3'4'0'20240817
                                         ~^
../../backends/imgui_impl_glfw.cpp:649:47: warning: missing terminating ' character [-Winvalid-pp-token]
#if EMSCRIPTEN_USE_PORT_CONTRIB_GLFW3 >= 3'4'0'20240817

This error is due to compiling with c++11 which does not support this syntax: this syntax was introduced 10 years ago with c++14...

I fixed it by removing the quotes and now CI is happy

On the CI commit:

I still think that this is a worthwhile addition otherwise the piece of code I added in (1) is never tested in CI run...

I agree but the comment doesn't seem to mention this:
"Build example_glfw_wgpu with Emscripten/Makefile" vs "Build example_glfw_wgpu with Emscripten/CMake"
If "build-essential" is required please add a comment to explain why (in file or commit) so we have a trace of it.

Thanks for writing and linking to that docs/Usage.md docs in your repository, this is helpful!

I have merged the OSX commit as ac2ad79 but not the CI commit yet. (You can freely force-push edits to same branchs and i'll merge the other commits), or since I am only expecting extra comments on the CI one you can write them here and I'll append them myself.

This error is due to compiling with c++11 which does not support this syntax: this syntax was introduced 10 years ago with c++14...

I have appended to your commit the same change to the other #if in the same file.
For now we generally stick to C++11 to maximize compatibility, as some projects and platforms are not supporting newer standards. Although for platform-specific code (and Emscripten is platform specific) we can rely on newer things if they are needed and useful. But if it's not needed better not raise a requirement needlessly.

I am also surprised that #if EMSCRIPTEN_USE_PORT_CONTRIB_GLFW3 >= 34020240817 is not warning if EMSCRIPTEN_USE_PORT_CONTRIB_GLFW3 is not defined. I don't know if it is because the code is not compiled will all warnings or if that became a silent thing in recentish versions of CPP proprocessor, or if I am misremembering?

I paid ultra close attention to code style. I hope I got it right this time around ;)

Thanks! I always tend to make small tweaks. If you are super curious you may compare my merged commit to yours (personally I use Git Fork I can easily see both and compare) but nothing crucial, don't sweat it.

Thank you @ocornut

I have force pushed a new commit with added comments as you suggested.

I am also surprised that #if EMSCRIPTEN_USE_PORT_CONTRIB_GLFW3 >= 34020240817 is not warning if EMSCRIPTEN_USE_PORT_CONTRIB_GLFW3 is not defined. I don't know if it is because the code is not compiled will all warnings or if that became a silent thing in recentish versions of CPP proprocessor, or if I am misremembering?

I suppose I am not an expert in CPP preprocessor behavior so maybe it might cause problems with some compilers?

Since we know for a fact that it works with the Emscripten compiler, maybe it would be safer to also protect this block? (other blocks are protected)

// ... Line 649 ...
#ifdef __EMSCRIPTEN__
#if EMSCRIPTEN_USE_PORT_CONTRIB_GLFW3 >= 34020240817
...
#endif
#endif

Merged both changes! Thank you!