Only show OSDs when media keys or hot keys are used

[WatchMkr]

For sliders or toggles in applets or Settings, the user has the feedback from the interface already. I think OSDs only show up with media keys or hot keys. I haven't thought of another scenario when they should.

[git-f0x]

Somewhat related, but the audio OSDs (input and output) should always show when a volume related key is pressed (though not sure if a microphone sensitivity key is present on many keyboards).
E.g. currently, when volume is at 100%, pressing volume up won't show the OSD (to confirm that it's at 100%).

[leb-kuchen]

KDE also has this issue, so I do not think, it is high priority.

[wiiznokes]

Somewhat related, but the audio OSDs (input and output) should always show when a volume related key is pressed (though not sure if a microphone sensitivity key is present on many keyboards). E.g. currently, when volume is at 100%, pressing volume up won't show the OSD (to confirm that it's at 100%).

The osd should subscribe to the keyboard event, and display accordingly then. This should be simple to do