I’m based in Europe and am amazed at a lot of the stuff talked about here. I’ve seen a few posts about notice periods being optional and employers just violating that. In Ireland notice periods are built into our contracts (to leave my current work I need to give 1 month). It can be awkward but if you get a new job offer both current and new employers legally have to allow it. If you get fired immediately after handing in a notice you can sue them in the Labour courts.