That is just an abstract example, because I use it many times. Now its raining errors in my site 
When you type
If($os) {}
It will now give an error if $os doesn’t exist.
Th same with:
It didnt throw an error in php 7.4 / Kirby 3.7
I didnt see it between the list changes of Kirby 3.8?
When I update to php 8 and kirby 3.8 It throws the error. Any ideas?
It works as an equivalent of isset($object) I just learned.
Should I change this everywhere now?