NOT responsible for bricked device!!! Proceed with caution and at your own risk. Linux/Ubuntu/debian is absolutely necessary for this process. No other ways for it.
NOT for the new Magisk v25 DO NOT DO THIS if you have installed Magisk v25 and have avb intact. Read the second paragraph again twice PLEASE!
Credit goes to NOT ME! ! ! ((Lebigmac has this
If you can't get this script to work on your device check out the brand new sophisticated superrepack tool by @munjeni line SystemRW / SuperRW (feat. MakeRW) v1.32 by lebigmac NEW VERSION COMING SOON! STAY TUNED!;)(y) ANY TALENTED DEVELOPERS...
forum.xda-developers.com
)(mines better in my opinion but I used his packages soo all to him everybody)) You should check these files out. Flash rw25.zip (I edited size of available space to agree with our ROM.) in twrp or OFox. An error will occur! Don't panic! Do not exit twrp/OFox. Unzip systemrw_1.32_bundle.zip in Linux/Ubuntu and run the sysrw script from the unzipped folder. From there it will dump your images from system, vendor, product, system_ext and create a super_fixed.bin(fastboot flashable) and then the script will flash to your device.
If you want clean then factory reset and wipe data, otherwise reboot and start uninstalling.
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warning

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If your device gets stuck in bootloop then flash stock vbmeta and vbmeta_system images with the flags --disable-verity --disable-verification. All will boot fine after that. (Again no Magisk v25. The new coding fails both ways.)
After all is said and done then start uninstalling packages, and or adding packages to your mounted /,/system,/vendor, etc by using terminal in recovery by advanced menu and mount then by typing
mount -o remount,rw /
" Same as above but with " /System_root, not /
Same as above but with /Product,. Etc,etc
After such you can add packages to product or system to get apps to install to system. Make sure you install the app first In android before you want to move it to system so it is initiated for your device
Just look in data/data in android os to find out which packages you should copy. (I check dates to see which of my apps I installed latest and go from there.) Then in twrp copy your apk and any lib or lib 64 to a newly created system/apps/selectedApp folder. after you copy the files, rename the folder you just copied to the system/product dir to the name of the app In camelBack type. That means the first word of the folder should all be lowercase and every word after that should start with a capital.
E.g. googleCalendar novaLauncher googleChromeBeta
So on and so on.
After everything wipe caches.
Whoop whoop!! All gravy baby now you can do anything your heart contents to.
((AGAIN I cannot stress this enough. NO MAGISK v25 NO No NO no NO No no!) Find another way for Magisk v25)