Seems to be a rare problem.
Finally I did a clean install with 10.9.5.
Sure, with Apple software the permanent certificate trouble.
Set the date to 2021 and go.
Finished, ... but the crash problem persisted.
I thought, this could have to do with a general problem in Mavericks.
And what has changed are the certificates.
OK, set date back to 2021, and the crash problem has gone directly. No crashes anymore.
Set date again to 2023, again crashes.
But after all, I cannot say, what a mix of problems it could be.
Because, the crashes every 10 secs comes aside with a 5-10 sec delay by opening any document.
And this behavior was the same with 2021-date and no crashes.
OK, finally, I erased the SSD again and did a CCC clone, back from my backup.
Restart and suddenly it runs without crashing and actual 2023 date.
so, really I dont know. But I know that I recognized this problem already some times earlier,
but it self resolved by any action.
I thought, that NVRAM could have influence, because I worked with Mojave and Monterey these days.
But I deleted the NVRAM serveral times.
I also did settings with timezone, because the turkish time is incorrect in Mavericks.
After all no idea. All I know is, revisiond has to do with the problems.
Finally I have copied the backup back and at least it works without crashes.
Still have to check the delays once more.
But as an old Mavericks lover, I get doubts, that working with 10.9 is still possible today
in every circumstance. And I dont like (aside of security) many of the progessions in OS today.
The permanent systemupdates today and incompatibilities that it generates makes me sad.
Compare, Windows7 still gets security updates today for customers.
I would wish a Snow Leopard 10.6.5 (no Appstore and no more feature updates anymore) with a
modern security architecture. Light and fast. Not more, not less.
Nice weekend