On your phone's recovery screen, navigate using volume buttons and the power button:
This method scares many users, but if you follow the steps precisely, it is perfectly safe. lineage os update without losing data
Then came the moment of truth. He didn't click 'Wipe.' That was the trap. For a "Dirty Flash," as the forums called it, you had to be surgical. He navigated to the 'Install' menu and selected the new LineageOS .zip file he’d downloaded. On your phone's recovery screen, navigate using volume
Follow this guide, and you can enjoy the latest security patches, features, and kernel improvements without the headache of re-setting up your phone. Happy flashing. For a "Dirty Flash," as the forums called
If you have Magisk (root), you must re-flash the Magisk .zip after the ROM but before rebooting. If you reboot without Magisk, root is gone (safe but annoying).
LineageOS includes a privacy-focused backup tool called SeedVault. It is your best friend.