I think this is a bug involving volume and balance sliders.

Audacity 3 Help Forum Windows
2

I thought I couldn’t make this happen - but some testing gave me these simple STRs (steps to reproduce)

  1. Open Project-1
  2. Ctrl+N to open new project: Project-2
  3. Observe project-2 is fully functional
  4. now just move your cursor, without clicking, over the Meter toolbars meter/slider section in Project-1
  5. Observe: Project-1 is moved the top and Project-2 is (partially) hidden behind it
  6. Now click in the visible part of Project-2
  7. Observe: Project 2 becomes active BUT remains partially hidden behind the now inactive Project-1

No other part of the Project-1 window causes this - not even the mic and speaker buttons in the Meter toolbars.

This is ringing some bells for me, I seem to recall that this mat be an already logged big - I’ll have to try to find it.

It’s also a regression somewhere between 2.0.0 and 2.4.2 - there it acts on the old Mixer toolbar in Project-1.

UPDATE
Found it

Windows: Hovering over the meters of an unfocussed project window brings that window to the front - original project retains focus #4094
https://github.com/audacity/audacity/issues/4094

See also this earlier Forum post that originally reported this:
https://forum.audacityteam.org/t/unwanted-switches-between-multiple-open-projects/66306/3

Peter