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I honestly don't know. You need to check datasheets on what, if anything, is different.
The released firmware (master) is very stable and have been without problems AFAIK since release.
The develop branch is what it's named, a branch that is in (slow) development. It is actually a quite big rewrite of the released (master) code. It's done by other contributors. They are working on adding some cool functions like autozoom, multiple sensors per MCU board and more. But again, it is an open source development branch.
AMG8833 worked with ESP32 but not with nRF52. I made some edits and fixed so it also works with nRF52 based boards.