Havent gone to 11 stable to rule this out, I think I should, but too much work to undo
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That's the nice thing in the case of RPi, the all system is installed on an SD card, what is easy to replace.
Why you don't simple use an another SD card to try another versions?
I have a card with the latest LE 11 stable (in the case if the LE12 beta have any serious bug - doesn't got any yet...) and another card for playing with the new beta versions.