#PHP 8.1

I think we should move any of the forgotten/missed conversions from this issue to a spin-off.

Thanks Alex! I did rebase on top of 11.x and reverted all unrelated changes

I don't understand why serialize() is being used here and there doesn't appear to be an explanation either in the MR or the issue summary - can't think of any situation where we'd want to do that either.

Removed cache as this kind of checks should be cached statically, also removed useless logging of error

I see no reason to use cache except of static variable because this check should happen only once while PHP is running