Unfortunately Active or Top just serves me the exact same posts I scrolled through previously in the day. Not sure if it’s an app issue or just a lack of content on lemmy overall.

If you’re using Sync, it’s the three dots on any post or comment, then Filter. You can choose to filter (block) the user, the community, the linked website, or the entire instance hosting it.

Three dots usually indicate “options” or “settings” when using Android. I’d invite you to tap those buttons any time you see them and learn more about the tools you are using.

It’s the same as a PID in any device that has a heater?

Whether it’s a $100 3d printer or a $60k seven stage SMD oven, if it has a heater it has a PID controller. It just tells hot thing how hot to get and how to get that hot.