Cannot delete conditional activation group

Hello!
Thank you for fixing bugs :D.
Note: Before bug reporting, please make sure you have tried the latest (alpha) version of BetterTouchTool and that you have already tried to restart your system :-). If you encounter a crash, please attach a crash log from the macOS Console.app from the "User Diagnostic Reports" section.
BetterTouchTool_2020-12-11-115126_BigMac.crash (106.6 KB)

Describe the bug
A clear and concise description of what the bug is.
I have an empty conditional activation group called "test", I want to delete it but when I try to do so, BetterTouchTool crashes.

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

Screenshots
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Device information:

  • Type of Mac: MacBook Pro 2019 "15, 2.6 i7, 16 GB DDR4
  • macOS version: macOS Big Sur 11.0.1
  • BetterTouchTool version: (please post the exact version - not just "the latest one")
    Alpha version, 3.510

Additional information (e.g. StackTraces, related issues, screenshots, workarounds, etc.):