(yes, I use the option to get the Macintosh main buttons).
I tried an 3.6.0 alpha before 3.5.1 (again, I have my reasons), but the builtin theme there looked almost as bad as the upper screenshot, except I got yellow as the background colour in a number of widgets instead of green or red, and the volume sliders were black rectangles unless I hovered the mouse over them.
For reference, here’s how the classic theme looks in the 3.4.0 alpha build that I’ve been using until now:
Now that’s what I consider a “pro” colour palette… (I also managed not to get the DE top panel thingy in the screenshot this time).
A bit off-topic here, but could the intruding colours be a result of some CLUT/OpenGL issue? I’m running this on a rather old distro but the compiler toolchain, Mesa and everything else that I think could be related are local builds of recent versions; wxWidgets is Audacity’s own version … but built against the hosts GTk2. I can’t find any information if 3.4 or 3.5 and up should use GTk3 as the wx engine?