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Posting information on test builds
This thread has been created specifically for posting information on official /e/OS builds.
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Please do not post information or links to /e/OS test builds on the forum.
The test builds are as yet untested and under development, and may in some cases cause user devices to soft brick.
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Remember not all users who come to this forum are experts in installing and formatting custom ROMs and can end up seriously damaging their devices by trying out these test builds
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Just tried to upgrade my Fairphone 3+ (not rooted) through the /e/ recovery using ADB Sideload – from /e/OS 1.17-s-dev to e-1.19.1-t-20240113373116-dev-FP3 using the download from https://images.ecloud.global/dev/FP3/ I went this way going from Q to S before, but this time I’m stuck here (I chose to ignore the signature verification failure):
I downloaded the zip from https://images.ecloud.global/dev/FP3/ again on a different computer, but the error(s) remain identical. Am I using an all wrong download?
UPDATE: SOLVED by AnotherElk’s reply (see below)
Saludos:
Vendor Name: Xiaomi
Device name: Mi 10T Lite 5G
Device CodeName: gauguin
Version of /e/OS previously: e-1.18-s
Device not rooted
Updated OTA
Thanks
Vendor Name - Samsung
Device name - S10
Device CodeName - beyondlte
Version of /e/OS or Stock which existed previously
E18s
Is the device Rooted / Not rooted - Not Rooted
Fairphone | FP3+ | FP3 | previously on /e/OS 1.17-s-20231111351092-dev-FP3 | not rooted
All data seems to have been taken over, cannot find any data loss in phone app, calendar nor messages. Thank you folks!
FP3 upgrade from 1.17-S to 1.19.1-T
Went through /e/ recovery and used ADB sideload to install the upgrade from the computer. (Eventually) Used the download link @AnotherElk suggested (direct download shortcut to save you having to sort out the back slashes size: 1.1 GB). Took just a single-digit number of minutes to install. A bit doubtful at the end when the FP3 recovery display’s bottom line just read (step) “2/2” and no (further) confirmation that install was completed. Just went back to the recovery home screen and rebooted into system, and there it was booting into Android 13.
P.S.: Unfortunately the Recovery still would not offer me any option other than installing through ADB Sideload. No SD card option (although portable storage SD card is in the device) shown, neither internal storage.
I’ve tried that now both with the internal storage and the SD (first at the top level of the file tree, then in the Downloads folder – with both IS and SD), but no difference. Now given that this is the installation file that is now already installed, it might not qualify as “compatible” anymore? Might try again with the next smaller update.
Impossible to upgrade. When download is finished, package verification starts and immediatly an installation error is issued.
I try that : Issues with the Updater and a solution without any success.
FP2, not rooted, Open Launcher 1.18. → 1.19.1-r
All fine
Tested: MullvadVPN, Signal, Firefox, FreeOTP+, KeePassDX, Aurora, f-droid, easybank app
Especially the bug in the Emailclient (see feedback 1.18) is solved - Cheers!
Posting information on test builds
SOLVED by AnotherElk’s reply (see below) 
Thank you folks! 
- Cheers!