I now had the second user with 26.2. complaining about a hang in my app. The hang occurs when the first AppleScript for Mail is run. Here is the relevant section from the process analysis in Activity Monitor:
+ 2443 OSACompile (in OpenScripting) + 52 [0x1b32b30f4]
+ 2443 SecurityPolicyTestDescriptor (in OpenScripting) + 152 [0x1b32a2284]
+ 2443 _SecurityPolicyTest(char const*, void const*, unsigned long) (in OpenScripting) + 332 [0x1b32a2118]
+ 2443 InterpreterSecurity_ScanBuffer (in libInterpreterSecurity.dylib) + 112 [0x28c149304]
+ 2443 -[InterpreterSecurity scanData:withSourceURL:] (in libInterpreterSecurity.dylib) + 164 [0x28c148db4]
+ 2443 -[XProtectScan beginAnalysisWithFeedback:] (in XprotectFramework) + 544 [0x1d35a1e58]
+ 2443 -[XPMalwareEvaluation initWithData:assessmentClass:] (in XprotectFramework) + 92 [0x1d359ada4]
+ 2443 -[XPMalwareEvaluation initWithRuleString:withExtraRules:withURL:withData:withAssessmentClass:feedback:] (in XprotectFramework) + 36 [0x1d359b2a8]
My app is correctly signed and notarised. The first user had to completely uninstall/reinstall the app and the everything worked again.
Why does this happen? How can the problem be fixed?