I have a Samsung Galaxy Tab 3 (GT-P5210GNYXAR) currently with NO OS (I completely wiped the tablet in TWRP.)
However, I did root the device, so now it has the TWRP thing. I tried installing the superSU OS I used to root android OS, no luck. I have not tried reinstalling the factory OS because the download time takes 2 hours.
I'm trying to install Ubuntu onto this tablet with a windows computer (that's for a different question) but
fastboot devices doesn't show the tablet.
adb devices does, however it says it is "unauthorized" and I don't know how to authorize it without an OS.
Is there some TWRP-specific program or something?
I tried downloading the stock rom from a website however the download was too slow (because I'm not paying for premium) and the download failed. However, I will retry tomorrow and use Odin or Heimdall.