Get heimdall:

sudo apt install heimdall

Get TWRP.

Boot into download mode: Power+Home+Volume Down. At the warning screen confirm by pressing Volume Up.

Install TWRP:

heimdall flash --RECOVERY twrp-3.3.1-0-hero2lte.img --no-reboot

Acquire Android 10.0 image from here.

Boot in to TWRP with Power+Home+Volume Up.

Load the image:

adb push PixelExperience_hero2lte-10.0-20200125-1815-UNOFFICIAL.zip /

Install the image by using Install and browing to the image you pushed.

Random copy-pasta that I didn't type set

Install Heimdall:

sudo apt install heimdall-flash Install lz4 (you will need this later to uncompress files):

sudo apt install liblz4-tool Unzip all the files from the firmware file (which, in my case, is called G965FXXU1BRF8.zip. This is a little like unpacking Russian dolls given that there’s a zip that contains tar.md5 files which contain lz4 files. The following commands will extract everything (this may take some time):

unzip G965FXXU1BRF8.zip -d firmware && cd firmware for f in .tar; do tar xf $f; done lz4 -dm .lz4 You should now have a bunch of files. The important ones end in .img and .bin. These are what we’re going to flash onto the partitions on your phone using Heimdall. If you want to jump right into doing that without understanding how we know how to map the files to the partitions, you can safely jump to Step 9 now. Otherwise, read on and learn…

To find out where we need to flash the various files we have, we need to ask Heimdall to inspect our phone and dump a Partition Information Table (PIT) file for us. To do this, first connect your phone to your computer via USB and boot the phone into Download Mode (hold down the power, volume down, and Bixby buttons - that’s the button on the top-right, along with the second and third buttons from the top on the left). When you see the Download Mode splash screen, press the Volume Up button as instructed to enter Download Mode.

Test the connection:

heimdall detect Dump the PIT file using Heimdall. (Note: your phone will reboot after this. Enter Download Mode again using the technique you learned in Step 5):

heimdall print-pit > phone.pit Open up phone.pit in a text editor and search for the names of the extracted files in Step 3 that end with .img and .bin. Note the corresponding Partition Name values as those are what you will be using in the next step as the names of the flags to the heimdall flash command.

Flash the firmware using Heimdall (your partition name -> flash filename mappings may vary. I’d highly recommend not skipping Steps 4-8 above and confirming that the mappings in your PIT file match before executing the following command):

sudo heimdall flash --BOOT boot.img --CACHE cache.img --CM cm.bin --DQMDBG dqmdbg.img --HIDDEN hidden.img --KEYSTORAGE keystorage.bin --RADIO modem.bin --CP_DEBUG modem_debug.bin --ODM odm.img --OMR omr.img --PARAM param.bin --RECOVERY recovery.img --BOOTLOADER sboot.bin --SYSTEM system.img --UP_PARAM up_param.bin --USERDATA userdata.img --VENDOR vendor.img