[Galaxy Tab S2 Android Development] metterschling:
Frequently Asked Questions. You MUST READ this before posting any questions. Thank you.

Question	Answer
Q1. Can I build this ROM for myself? Where are the source and kernel source files?	A1. Yes, you can. The source files are listed below.

Kernel

https://github.com/metterschlg/android_kernel_samsung_universal5433

Device Tree

https://github.com/metterschlg/android_device_samsung_gts2-common-selinux

https://github.com/metterschlg/android_device_samsung_gts28ltexx

Vendor

https://github.com/metterschlg/proprietary_vendor_samsung

Build manifest can be found at

https://github.com/metterschlg/local_manifests/blob/lineage-20/gts28ltexx.xml

Build environment setup is documented (as code) at

https://github.com/metterschlg/los-devel-scripts
Q2. Is this ROM suitable as a daily driver?	A2. It might be, depending on your requirements. You would need to try it yourself, with your preferred apps, to see if suits your purposes. I've been using it myself since December 2022 with no major issues.
Q3. What do I do if my app xyz doesn't work?	A3. I can't help diagnose problems with random apps I know nothing about. If the app is critically important to you and it doesn't work on this ROM, go back to a ROM where it did work.
Q4. Why is this ROM laggy and/or buggy?	A4. The device will be noticeably slower if you're using any Gapps package. Consider going gapps-free. A lot of apps will work without Google's services, or there exist alternatives that will. Check out F-Droid, Aurora Store, NewPipe, etc.
Q5. What TWRP should I use?	A5. I use official TWRP 3.6.1_9. Get it from

https://twrp.me/samsung/samsunggalaxytabs280ltexx2015.html

Please note that ADB is broken in this version as it is in all newer releases. Newer releases haven't worked for me - your mileage might vary.
Q6. Why should I use this ROM?	A6. You don't have to! If you don't like it, go back to your old ROM.
Q7. Will you offer monthly updates with security patches?	A7. I plan to do so. I will try to update the ROM with the monthly security patches after LineageOS has released them, free time permitting. Each monthly build will be quickly tested to make sure the ROM still works, before it's made available (which might in some cases delay the release).
Q8. I'm a newbie. Can you provide step by step instructions?	A8. We simply don't have the time to do this, but there are lots of tutorials, videos, etc online showing how to flash custom ROMs and how to deal with common problems. Newbie questions are also accepted in the XDA General Questions and Answers forum. Having said that, @pflyaz has kindly make a guide in post #37.
Q9. Can I report a bug with respect to the ROM?	A9. Yes, but you need to supply the following information. If you don't, I won't look at it.

Provide an adb logcat of the problem, and if possible describe how to reproduce it. Note that I can't help if it involves downloading any app I don't already use that requires payment or creating a userid/password.

To get a logcat, open a terminal window on your PC, connect your device to it via USB, and do this:

# clear the logcat first
adb logcat -c
# start logcat trace
adb logcat > problem.txt
# reproduce problem
# wait until problem has occurred,
# then stop trace by hitting ctrl-c then zip the problem.txt file
# before uploading it.

Q10. How long will you build 20 for this device?	A10. For now, 20 will be built for all of 2024. After that, the team of gts2 developers will make a decision depending on a number of factors.
Q11. Do I need to erase everything and format my data before installing this ROM for the first time?	A11. Under most circumstances, yes.

If you're coming from stock Samsung Android, or an earlier version of LineageOS, or a different custom ROM, you MUST 'clean flash': boot to TWRP recovery, wipe system, data, dalvik/art cache, and cache partitions, then Format Data, then install this ROM.

If you are coming from stock Samsung Android, you must ensure that you are first upgrading to the last release 7.0 version, otherwise you won't be able to install this ROM.

If you don't do this you're likely to run into problems, such as getting stuck at the boot animation for more than 5 minutes.
Q12. What Gapps should I use?	A12. Your choice! There are several well-known Gapps packages, such as NikGapps, BiTGapps, and MindTheGapps. Do your own research as to what is the most reliable gapps option for you.

I recommend installing the SMALLEST version of any of these, preferably with just the minimum Google services needed to access the Play Store and run apps that depend on Google services.

You could also consider Google alternatives, such as Aurora Store, which mirrors the Google Play Store apps but doesn't need any Google services itself. Many Play Store apps do not actually depend on Google services.

If you are going to install any Gapps package, follow the installation instructions given for that particular package.
Q13. I'm having problems with Gapps. Can you tell me why it's not working?	A13. I can't answer any questions about Gapps, because I don't use them. Ask your questions on the XDA thread for the Gapps package you're using.
Q14. Why isn't my post answered?	A14. There are several possible reasons: the question is answered in the FAQ (in which case it will be ignored completely); or it involves apps or operating systems that I don't use; or it's about Gapps, which I don't use; or I simply have not had time to answer any questions.
Q15. What speed up/optimization tips do you suggest?	A15. These steps can make a big difference to performance:

Turn off animations. Go to Settings > System > Developer options, scroll down to the Drawing section, and set Window, Transition and Animator scale all to "Animation off".

Don't install Gapps unless you depend on something that only Google is providing. Use Aurora Store to get your preferred Play Store apps - they will all be available on Aurora Store. You can choose to access this anonymously or use a Google account.

Don't run more than two apps at the same time. You can probably listen to music in the background and use a web browser at the same time.

Use a web browser with built-in adblock and privacy features, such as Brave.

Use NewPipe to watch your streaming content. It has built in adblock so you don't have to watch forced ads.

Look for apps that are open source, ad-free and lightweight.

Q16. Does this ROM support Magisk so I can root my device?	A16. Magisk works with other device variants of this ROM as reported by pre-Alpha testers, but that could change with any revision and changes by Google. However I can't help with any related issues. Direct any questions about Magisk to the XDA Magisk forum.
Q17. Will this ROM ever become official?	A17. Never. Official maintainers have onerous responsibilities, and I know my device trees, code organization and git commits will NOT meet LineageOS standards. I'm not able or willing to take on the responsibilities and commit the extra time to supporting an official build.
Q18. What is the difference between this ROM and others?	A18. This ROM tries to be pure LineageOS with little or no modification. Other ROMs may come with a different UI, different bundled apps, etc.
Q19. Will there be any major 20 code modifications in the future?	A19. I don't anticipate any major modifications. There may be some slight tweaking to the SEpolicy, small bug fixes and minor code cleanup, but all the hard work - getting the ROM up and running, and fixing all the major bugs - has been done. This doesn't mean the code is perfect or well organized, but I won't be making any major changes.
Q20. Why did you fork the trees?	A20. I wanted my own private branch where I could make changes that would only affect my own personal builds.
Q21. Can you build a variant of this device? For example, a S-pen version?	A21. I cannot and will not try to build for a variant device if I don't physically have that device. I have to be able to boot and test it myself, and there's no guarantee that I can get those variant features working. So I will NEVER build T710, T810 and T815.
Q22. Does this ROM have any wifi connection issues?	A22. This ROM's wifi has been stable on the specified device ever since lpedia and retiredtab determined the root cause of the wifi problems back in July 2021 and re-installed the original S2 network 'blobs' with LOS 17.1.

There has no been no fix for the “Connected to device. Can’t provide internet” (CPI) that occurs for some testers. I am not affected as I use the ROM without gapps and only a few installed apps.

DO NOT ASK when this will be fixed. If/when it is fixed, it will be announced public in this thread.

If you have a lot of apps installed, you may run into CPI as we suspect it's possibly a slow memory leak. Depending on how many apps you have installed CPI may show up in 14 days. The only way to "fix" CPI is to reboot.

CPI may also show up if you have even just one app that somehow triggers a huge/large memory leak. Again, the only "fix" is to reboot.

We've spent a lot of time trying various kernel binder patches and updating the binder code as much as possible, but some users, NOT all, still run into CPI. Since I am using F-Doid and minimal apps, I never run into CPI like some pre ALPHA testers.
Q23. Is this ROM secure so I can do financial transactions?	A23. Although Android monthly security patches do improve general security, this ROM's outdated kernel and old proprietary vendor blobs/drivers will NEVER get updates of any kind, and could have significant security holes.

In addition, although the ROM is SElinux enforcing, there's a good chance that the rules written (about 800+ lines of code) have some errors.

If the device is rooted, this would further weaken the security.

With this information, it's up to you to make an informed decision about whether you trust this ROM to be secure enough for your financial transactions.
Q24. Okay, I understand the consequences and willing to take the risks outlined, now where can I find the BETA ROM?	A24. Downloads are at

https://sourceforge.net/projects/los4sgt/files/los20/

If your initial enforcing build install does not have working RIL, you might need to fix SELinux labeling of your EFS partition. To do so, use ADB in root mode. Please note that ADB root needs to be enabled in the developer options of your device. Then use the following commands from a PC connected via ADB:

adb root
adb shell
# Check if SELinux relabeling is required, do not modify anything
restorecon -R -v -n /efs
# If you see some "Relabeling..." output, run the real relabeling
restorecon -R -v /efs