Using XOJO 2018R4
I have an app that shows some photos in a Canvas as preview.
High Sierra all nice and smooth , same code in Mojave is crashing the app straight with the error :
[quote]Date/Time: 2018-12-20 17:26:25.392 +0100
OS Version: Mac OS X 10.14.2 (18C54)
Report Version: 12
Time Awake Since Boot: 2200 seconds
System Integrity Protection: enabled
Crashed Thread: 0 Dispatch queue: com.apple.main-thread
Exception Type: EXC_BAD_INSTRUCTION (SIGILL)
Exception Codes: 0x0000000000000001, 0x0000000000000000
Exception Note: EXC_CORPSE_NOTIFY
Termination Signal: Illegal instruction: 4
Termination Reason: Namespace SIGNAL, Code 0x4
Terminating Process: exc handler 
Application Specific Information:
Crashing on exception: The window has been marked as needing another Display Window pass, but it has already had more Display Window passes than there are views in the window.[/quote]
Any idea what this could be ?
So doing some tests , in High Sierra , the Modal window shows, loads the pictures and displays and all, while in Mojave same code is calling Paint event several it crashes with that error .
Did something changed in the last update related to Canvas ? and Mojave ?