What I'm looking for is a tool that would be able to detect and visualize keyboard actions when recording video. I imagine a resize-able always-on-top window showing current keyboard layout and actions.
The use case is any situation when in a bug report, response of tested software to keyboard needs to be described in detail. Video is often good choice except that most of the time either sound is not available at all, or vocal description of keyboard actions might be insufficient or even disturbing.
I'm not sure if such software exists, but it would be useful. Any tips? (My platform is Windows but I'd be happy to have covered more platforms in this Q. And of course, free/libre- software is strongly preferred.)