Thanks a lot everyone that helps on Oreo, great job 
I did a factory reset, upgrade Twrp, then use it to instal Lineage, Gapps pico and Su. Everything works well!
The only two problems I have are known bugs: Exchange that is missing, and the camera (Open Camera for me) that cannot record video. Appart from this, it is perfect 
Than again
A post was merged into an existing topic: Easy info about LineageOS 14.1 features not working in 15.1 (e.g. Exchange)?
I upgraded tonight, it seems to work properly. I flashed su-addon and F-Droid privileged extension (was that necessary after wiping system partition?) right after the Oreo image.
Boot time has improved a lot.
Yes, naturally, they live in system.
I successfully upgraded my encrypted phone without GApps and have not lost any data .
However, two of my most frequently used apps crash frequently 
, namely, K9-Mail and OSMAnd (installed via F-Droid). I already reinstalled K9-Mail but now I am not even able to launch it at all – before, it crashed whenever I opened an email, so I was at least able to access my inbox.
Does anyone have a suggestion what to do? Do you know whether it is Lineage or App related?
My K9-Mail works as before… I use LOS+microg but that should not Change anything, i guess.
Since upgrading to 15.1, I notice that my K-9 Mail sometimes has the status “synchronization disabled”. I haven’t had that at 14.1 yet. Has anyone had a similar experience?
Workaround: Disable- and Enable mobile data.
I also observed this with 14.1, since adding K9 as an exception in battery saving optimisation it never happened again.
I can make photo’s, but can’t record video’s, “could not start media recorder can’t start video recording” is the error. Anyone facing the same issues?
Thank you very much for the info!! Will wait fort an update then
K-9 development is rather stalled.
p≡p is a K-9 fork with material design and opportunistic GPG. Works fine for me on Oreo thus far.
EDIT: It is free on F-Droid, btw.
Hi. I tried to update Official LineageOS 14.1 to 15.1 via TWRP following instructions founded
here.
First time I wiped system and cache before flashing, but I got endless loop on system reboot.
Second time I wipe data too, but still got endless loop on system reboot.
I tried to restore the backup I had done previously, but I got un error.
Tried again after a fresh dowload and SHA256 verification, but still endless loop until battery go down…
May someone help me please?
Great job done, thanks to all, especially @chrmhoffmann !
My upgrade didn’t run so smoothly yet:
I’ve read that @lklaus faced something similar, and continued later with wiped data partition.
Has anyone had the same experience, and might give some advice?
Later this afternoon I’ll try again to run the upgrade.
This does look stalled to me:
35 pull requests?
The last release was a pre-release on April 2 2018?
Plus, as I said, it doesn’t have material design. You just need to see the interface to know how out of date this software is. Its like from pre-2015. Terrible.
To each their own, but this is why I prefer pEp. Which seems to work well on Oreo, so its worth mentioning.
Was your FP2 on the charger? If yes, do the reboot without charger with full battery.
Yes, it was on the charger. Thx for the hint, I’ll try it without.
Judging a project by their opened PRs is superficial, honestly. Specially for a a non-lucrative, independent, open-source project run by volunteers. Definitely not fair. Latest commit 2 days ago, BTW.
Again, superficial. C’mon, user interface is outdated, sure, but code isn’t. You can’t judge code by its UI: not all developers can (or should, anyway) build good UIs. Furthermore, K-9 mail is a quite developed fork of the AOSP pre-ICS era mail client. It’s quite the work to overhaul a UI of that age, specially on ever-changing Android.
BTW, pEp is built on top of K-9. They deserve some respect for that quantity of years working on such a good software, no matter if you like their UI or not.