BTT unhandled exception: *** -[__NSCFString stringByAppendingString:]: nil argument|

Since upgrading to macOS 26.1 BTT is crashing when launching. I have rebooted and enabled safe mode (defaults write com.hegenberg.BetterTouchTool BTTSafeModeEnabled YES) and BTT still crashes. Moving the configuration sqlite db from Application Support allows BTT to launch (without my configurations).

Launching from the command line it looks like it might be an a problem with one of my AppleScripts but I’m unsure how to resolve that.

➜ /Applications/BetterTouchTool.app/Contents/MacOS/BetterTouchTool  
2025-11-18 14:12:04.261 BetterTouchTool[17882:65208] 🔧 Adding crash protection to OSAScriptView setTypingAttributes:
2025-11-18 14:12:04.262 BetterTouchTool[17882:65208] ✅ Successfully added crash protection to OSAScriptView setTypingAttributes:
*** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '*** -[__NSCFString stringByAppendingString:]: nil argument'
*** First throw call stack:
(
	0   CoreFoundation                      0x000000019ac898dc __exceptionPreprocess + 176
	1   libobjc.A.dylib                     0x000000019a762418 objc_exception_throw + 88
	2   Foundation                          0x000000019cebc794 -[NSString stringByAppendingFormat:] + 0
	3   BetterTouchTool                     0x0000000102a71aec BetterTouchTool + 88812
	4   BetterTouchTool                     0x0000000102a7f5c0 BetterTouchTool + 144832
	5   CoreFoundation                      0x000000019ac33484 __CFNOTIFICATIONCENTER_IS_CALLING_OUT_TO_AN_OBSERVER__ + 148
	6   CoreFoundation                      0x000000019ac97f34 ___CFXRegistrationPost_block_invoke + 92
	7   CoreFoundation                      0x000000019ac97e78 _CFXRegistrationPost + 436
	8   CoreFoundation                      0x000000019ac11f9c _CFXNotificationPost + 740
	9   Foundation                          0x000000019ce33308 -[NSNotificationCenter postNotificationName:object:userInfo:] + 88
	10  AppKit                              0x000000019f04ae74 -[NSApplication _postDidFinishNotification] + 284
	11  AppKit                              0x000000019f04ac24 -[NSApplication _sendFinishLaunchingNotification] + 172
	12  AppKit                              0x000000019f5c256c -[NSApplication(NSAppleEventHandling) _handleAEOpenEvent:] + 488
	13  AppKit                              0x000000019f5c5d70 -[NSApplication(NSAppleEventHandling) _handleCoreEvent:withReplyEvent:] + 488
	14  Foundation                          0x000000019cd80728 -[NSAppleEventManager dispatchRawAppleEvent:withRawReply:handlerRefCon:] + 316
	15  Foundation                          0x000000019c43f688 _NSAppleEventManagerGenericHandler + 80
	16  AE                                  0x00000001a2e580f4 _AppleEventsCheckInAppWithBlock + 13892
	17  AE                                  0x00000001a2e57a34 _AppleEventsCheckInAppWithBlock + 12164
	18  AE                                  0x00000001a2e510e8 aeProcessAppleEvent + 484
	19  HIToolbox                           0x00000001a764d7b8 AEProcessAppleEvent + 68
	20  AppKit                              0x000000019f0460f8 _DPSNextEvent + 1296
	21  AppKit                              0x000000019fb13f44 -[NSApplication(NSEventRouting) _nextEventMatchingEventMask:untilDate:inMode:dequeue:] + 688
	22  AppKit                              0x000000019fb13c50 -[NSApplication(NSEventRouting) nextEventMatchingMask:untilDate:inMode:dequeue:] + 72
	23  AppKit                              0x000000019f03e780 -[NSApplication run] + 368
	24  AppKit                              0x000000019f02a6dc NSApplicationMain + 880
	25  dyld                                0x000000019a7d5d54 start + 7184
)
libc++abi: terminate_handler unexpectedly threw an exception
[1]    17882 abort      /Applications/BetterTouchTool.app/Contents/MacOS/BetterTouchTool

Device information:

  • Type of Mac: Macbook Pro M3
  • macOS version: Tahoe 26.1
  • BetterTouchTool version: 5.750 and 5.759 after downloading update

Additional information (e.g. crash logs, related issues, etc.):

BetterTouchTool-2025-11-18-140652.ips (31.1 KB)

That is a tricky one because it seems to happen very early and the log doesn't really tell where. Would you be able to send the configuration sqlite files to me or does it contain private stuff? (andreas@folivora.ai)

btt_data_store.version_5_759_build_2025111503-wal
btt_data_store.version_5_759_build_2025111503
btt_data_store.version_5_759_build_2025111503-shm