Update : After several tries Ubuntu starts on my FP3.
I loved Meego Harmattan and my N9
I used a FP2 with UT, and liked UT
I used LineageOS on my FP3 (I don't like Android)
Now using SailfishOS on my XA2 (And love SailfishOS)
No I can use UT on my FP3, nice.
Next PureOS on my Librem 5 and Sailfish/UT/Mobian on my Pinephone