Honestly, it's a pretty informal process for me. 😅 I usually keep a list of known issues and things that need fixing, then test them as I go. Same goes for smaller issues but I usually just go and fix smaller things immediately anyways.
I guess it depends on the size of the project, though. When you're a solo dev or working with a small team, it's easy to get away with a less structured approach but it gets messy pretty quickly if the project is big.