Since a while I've been repeatedly interrupted by an alert window popping up to warn about a MigratorUIAgent not being able to start.
Clicking "Report" in the alert provided the following (redacted for brevity) information:
Process: MigratorUIAgent  Path: /Library/Application Support/Avira/MigratorUIAgent.app/Contents/MacOS/MigratorUIAgent Identifier: MigratorUIAgent Version: ??? Code Type: X86-64 (Native) Parent Process: ???  Responsible: MigratorUIAgent  ... OS Version: Mac OS X 10.11.6 (15G22010) ... Dyld Error Message: Symbol not found: _kSecGuestAttributeAudit ...
So, it's from Avira and it's very likely an incompatibility with my aging OS version, introduced in a recent Avira update.
I found no information on Avira's site (nor anywhere else for that matter), where instead I found out I cannot report the issue to them because that is not allowed to users of the free version. Oh well, in any case I expected a "go buy yourself a new Mac" response.
Since I did not want to remove Avira entirely, I headed inside the app package contents and tentatively renamed MigratorUIAgent to MigratorUIAgent.BROKEN or something like that.
I did not expect it to work, but it did. No more alerts and the rest of Avira keeps working without a complaint. So far so good.
But what is this MigratorUIAgent?
From the name and the periodicity of the alert, I suppose it's the auto update agent.
Does anyone know more about this process?