Logitech MX Mechanical, french Swiss mapping (Qwertz), $ is not corretly mapped


Describe the bug
When the "Logitech Keyboard Configuration" is enabled for my Logitech MX Mechanical (Swiss French / QWERTZ ISO layout), the $ key no longer types $. BTT captures it as a Logitech special key named "logi backslash" instead of passing it through to macOS.

On ISO keyboards this is the key next to Return, which is reported as the standard HID key "Keyboard \ and |" / "Non-US #". With the "Swiss French" input source, macOS normally turns it into $ (and £ with Shift). BTT seems to treat it as a Logitech-specific key and consumes it, even when no action is assigned to it.

What I already checked

  • Keyboard is in macOS mode (Fn+O); input source is Swiss French; keyboard type is ISO.
  • No key remapping in Logi Options+.
  • No BTT trigger is assigned to this key.

Affected input device:
Logitech MX Mechanical (Swiss French ISO layout), connected via Bluetooth

Device information:

  • Type of Mac: e.g. MacBook Pro 14" M3 Pro
  • macOS version: Golden Gate
  • BetterTouchTool version: 6.824

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

Logitech keyboard