Not sure if this is an issue with Chinchilla, interference from another addon or something entirely different.
I have "Quest Tracker" set to enabled, and use a custom position (vertical), and every time I log in/go from one zone to another, the quest tracker bumps down, as if completely disregarding the position I set in the options. Un-ticking and re-ticking "Enabled" moves it back to the set position, but I have to do this all the time.

Thanks in advance!

I'm inclined to say it's interference with other addons.

There was an issue prior to v2.9 where the tracker would reset to its default position when changing a zone due to some dodgy code in Blizzard's action bars (don't ask). I'm assuming you've got the latest update installed?

I have also recently noticed that some databroker display addons such as Bazooka and Chocolate Bar have been causing a few problems. If you have one of those, turn off any "readjust frames" or similarly worded options. That might do the trick but I can't guarantee anything.

Not using any of those, but I found out what was causing it: MoveAnything.
Which makes perfect sense, and I honestly don't know why I didn't look more into it before posting >.<
Luckily I could disable only the tracker part of MoveAnything and not the entire addon!
Thanks!