Warning “max_execution_time” / Cloning does not work / Error 500

Hi everybody,

I have the following error message for some time:
This host’s max_execution_time is set to 0 seconds – we generally recommend at least 60 seconds for running the Cloner. You may want to increase the max_execution_time in php.ini (or wherever your host supports PHP configuration updates) to avoid any timeout errors.
Of course, I′ve defined the max_execution_time much higher than zero.
In any case, cloning has worked so far (with this error) for about 5 sites…

But now, I guess since the last WordPress update, the cloning no longer works.

I get an error 500 immediately. A clone is created in the background, but only partially. I can call the clone later, but records are missing as well as some folders to uploads directory. (File premissions from uploads folder are on 755 …)

Is the error known?
Any idea what this can be?
Should I try the Pro version?

Many thanks for any support!
Best Regards,
Christian Fischereder