Linux HiDPI Support
My idea of how we should implement this
Audacity should respect the 'Gnome scaling factor' (this should fix gnome and unity installations, like for Ubuntu). For achieving this first we'll need to recompile with GTK3 widgets audacity (using a modified wxWidgets with GTK3 selected instead of GTK2).
I'll attach screenshots of audacity on my 4k resolution to show the problems in each of one:
Screenshots with GTK2
This is the normal build, as of 2.1.2 Audacity.
Screenshots with GTK3
With GTK3 the interface looks proportionate. The microphone monitor (Recording level) shows skewed, as the Playback level control also show the numbers in a strange place. Other control showing strange is the start of the timer (the button that says "Unpinned play/record Head (no key)").
Other controls look fine (like the Preferences dialog, a startup warning because wrong configured audio, and the soundwaves when opening a project of mine)