Mouse inputs anywhere in UI cause DAW VKB notes to not play in Surge XT

I’m using Surge XT ( GitHub - surge-synthesizer/surge: Synthesizer plug-in (previously released as Vember Audio Surge) ) which uses JUCE. Whenever I click anywhere (and hold) in the UI the DAW VKB stops working, in fact no keys do anything, for example in Reaper ESC closes the plugin window normally but if I click somewhere and press ESC the plugin windows doesn’t close.

I was told this doesn’t happen on some other OS (I think linux) so I’m posting this as a Windows question. I’m not too familiar with JUCE overall.

Surge XT has its own VKB which does work when something is being clicked.

Is there any good way to debug this? And can anyone else reproduce this?

My repro is this:

  1. Open Surge XT
  2. Play notes using the DAW VKB, works fine (may need to activate Send all keyboard input function)
  3. Start dragging slider and hold
  4. Play notes using the DAW VKB

Result: No notes are heard

Expected: The played notes are heard