[OnePlus 6 Questions & Answers] RusherDude:
Finally someone that seems to know stuff about this!

Yes, I have some questions if you have a min, I'm kinda confused with the A/B stuff :crying:.

1) So, "fastboot --set-active=a" or "fastboot --set-active=b" works everytime, or if the slot was "disabled" for some failed boot it won't work? if the latter is the case, can you enable them on command too?

2) At first boot, you're on slot A I guess, but what is on slot B? slot A replicated or nothing? if by mistake you screw up flashing on the first ever setup and the slot becomes disabled because it wont boot, if it switches to B and you never updated anything, will it find a system or not even a bootloader and be completely screwed???

3) how does TWRP flashing work on those setups? I see that you first have to boot TWRP and then inside TWRP flash the own TWRP, so it patches the kernel with TWRP. But I am reading that people claims that Magisk is needed in order to boot after flashing TWRP for some reason which doesn't make any sense. Why? isn't TWRP patched correctly into the kernel or this just doesn't work without Magisk for some random reason?

4) This is a noob question. I always used SuperSU, but I am seeing no talk about SuperSu on phones with A/B partition, it is not compatible anymore? To be honest I prefer it much more than magisk :(

5) What happens if you screw flashing on slot A, it disables slot A and reboots on slot B, and then you screw also on slot B? it disables it and then you boot up in fastboot or something, or not even that and you're kinda screwed? (only qualcomm mode?)

6) Any "hack" to evade the bootloader from changing slots if one became unusable, aka using the phone like the old ones? It seems like a nightmare if for some reason a boot fails because a minor screwup and suddently you find yourself trying to fix it.. on the other slot!!!! it sounds so confusing, and I don't know if the Pixel community didn't find this also confusing as hell and would preffer to just disable slot B permanenlty or something like that. It would be a great feature if you don't want seamless updates for we, flashers.

7) Any A/B detailed guide covering all these stuff and so? Checked OP6 and Pixels forums and what I'm finding is people following just a pattern of commands, but mostly nothing is explained on what to do if screwups happens, only "reflash from stock images and gone". I am really surprised to not see any community dominating the A/B partition still.. expected hacks like 6) or stuff to control the flow of the boot by our own flashing intentions and not the bootloader checks.

8) (added) How do update work in reality? I mean, when an automatic update comes and has to flash an OTA, it goes to the other slot and flashes it, but what if in that slot there was garbage? it would need a complete OTA and not an incremental one, right? And in the manual update scenario (disabling automatic, when phone asks for update), same would happen since everything would be flashed on the other slot, but complete OTA would be required right? or it won't check and will try to flash a incremental OTA over garbage and just fail :S.

Thanks a lot :fingers-crossed::good: