BTT Touchbar remains visible when it shouldn't

Describe the bug
I have a touchbar button (A) without key modifier and a button (B) with control key modifier defined and use the right shift key to toggle between the system default touchbar and the BTT touchbar (Toggle BTT Touch Bar). This works fine except for the following:

  • the BTT touchbar is disabled
  • hold the control key -> button B appears (correct, I guess)
  • additionally hold command -> button A appears (strange)
  • release command -> button B appears again (correct)
  • relase control -> button A appears (wrong, BTT should be off)
  • press right shift -> nothing happens, button A remains visible (weird but probably correct)
  • press right shift -> BTT touchbar is disabled (correct)

Affected input device (e.g. MacBook Trackpad, Magic Mouse/Trackpad, Touch Bar, etc.):

Device information:

  • Type of Mac: MacBook Pro 2018
  • macOS version: 10.13.6
  • BetterTouchTool version: 2.548