Just found it on the XDA forum. Unfortunately not R but Q. I would need a while until I install also the LOS-17.1 and eOS Q sources… I will start with T713, since I have this device and can test
There exists even an alpha version of LOS20 for the T813. Since I did not succeed with porting the T810 I will try the LOS-18.1 (Android 11) first and LOS-17.1 maybe
Yes @ronnz98, it’s “only” LOS 14.1 (Android 7), but much more privacy friendly than the original LOS. The OS is continuously supported (monthly) by an enthusiast and expert. I also install a MinMicroG package and mod the user interface, e.g. full gesture control.
I wasn’t successful with upgrading from Pie to Q eOS via adb sideload. But new install did work
Well it seems to work as outlined in XDA forum for LOS-17.1 Build:
Problems known to happen after a Dirty Installation​
A muddled up mess of a system. You are taking a rom and installing a newer rom with changes over the top of your old rom. Between these two periods of time during which you used your tablet and created data, changed system options, and used apps. This is absolutely increasing the risk of causing problems somewhere in the system/data partitions. Some people have luck with Dirty Flashing. However, it’s always hit-and-miss because of what we mentioned above about bug fixes breaking previously working functions. Dirty flashing doesn’t only create problems if the source code of the system data and the system settings of the new build are significantly different from those of your previous build. That’s not to say that Clean Installing won’t ever create problems, but only bugs present on a Cleanly Installed rom are relevant for development purposes.
* Clean Install: Fully wiping everything and installing the rom onto a fully clean system/data partition of the tablet.
Dirty Install: Installing the rom and GApps over top of the older rom to save time and not have to reinstall all the user apps and tweaking system and app settings that usually take a lot of time to set up as you like.
Bugs
The rom bootloops only after clean flashing. Force rebooting allows it to boot properly the second time and every time afterwards. See the FAQ’s above.
The cameras work, but with a delayed response, so they are impractical to use.
T719 & T819: RIL does not work at all.
However, Camera (and thus video) I did not get to work
Hi @ronnz98, I did a clean fresh install but after booting the system hangs on the animated e-logo. An additional factory reset did not bring any improvement either.
Maybe the source code of LineageOS 16.0 + 17.1 by dev @wickenberg’s helps?
The rom bootloops only after clean flashing. Force rebooting allows it to boot properly the second time and every time afterwards. See the FAQ’s above.