It should ask you if you want to save and re-open the current listers if that happens. There should be a checkbox in the message that tells you there was a problem. (Unless the process is in a state where it can't even display the message, which could happen if something like a shell extension corrupts memory or exhausts the GDI handles.)
I would focus on fixing the problem itself instead. Are any crash logs created? We may be able to use those to tell which exe/dll the problem is in:
Another possibility is that something on the system is incorrectly sending broadcast messages to all other windows, and happens to be sending a restart message to Opus.
A third possibility is that something is using the Windows Restart Manager to restart the program. (Usually, only installers do that.)