Looks nice! I've sent you an email with further instructions on the steps to contribute the code.
The problem that I see is that there seems to be nothing wrong with the code from ISPConfig, its like this for years now, it works fine on Debian...
Or he can contact the ISPConfig business support https://www.ispconfig.org/get-support/?type=ispconfig and I'm sure @Th0m can sort that out for...
This whole thing is basically not an ISPConfig issue, ISPConfig works fine according to the user. So I think Softaculous support should help him...
I don't think that reinstalling working PHP modules will help, it just might cause damage. There is no problem with these php modules as ISPConfig...
Then you must ask the Softaculous support, their docs claim that Softaculous uses the file /usr/local/softaculous/conf/custom.ini to load PHP...
Please change its content like this: extension=mysqlnd.so extension=mysqli.so extension=curl.so extension=soap.so extension=posix.so...
Ok, and what's in the file: /usr/local/softaculous/conf/custom.ini
Please post the output of the command: ls -la /usr/lib/php/20210902/
If you like to manually validate the dkim signature of an email, you can e.g. try this: https://github.com/kmille/dkim-verify
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