yashsingh1/xdaforums huggingface dataset:
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] AluminumTank:
Just wanted to confirm that I flashed the latest FW (10.3.12) on my Tmob today and booted up with no issues. Actually, it may have fixed a camera focus issue I was experiencing.
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] jhedfors:
Just to confirm - had you converted your TMobile to international prior, or were you running on TMobile firmware?
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] AluminumTank:
I had converted it to international prior.
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] jhedfors:
Important point - I thought that might be the case. Same here
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] niezam95:
can I install lineage os with oxygen os 11 as my base? or I need to downgrade to android 10 before the installation?
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] jhedfors:
I don't believe it works yet with the updated firmware
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] niezam95:
Alright..thanks..
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] dwardo:
Seems installing over OOS 11 it is on its way (see todays commit including : https://review.lineageos.org/c/LineageOS/android_device_oneplus_sdm845-common/+/315213)

Guess it will be finished when the installation instructions are updated and recommend being on Android 11
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] retry0001-coffee:
I'm confused about something. If I'm already using LOS on my 6T (Tmo edition), and I can't update the firmware because it's not for my device (unless I convert to international? But I actually use Tmo in the USA), and then the latest LOS ROM will require it at some point? Am I screwed?
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] jabashque:
No, not entirely. The changes to the device tree and kernel still keep compatibility with Q vendor+fw, but you'll lose ANT+ and DASH charging support. However, once lineage-19.x comes about, support for Q vendor+fw will be dropped.

EDIT: that being said, I converted my fajita to intl from tmo long ago. Benefits like roaming onto U.S. Cellular are still present because that's based on an IMEI whitelist, I think,.so it doesn't matter what you run on your phone.
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] retry0001-coffee:
I don't know what any of that is. For me phone working is a boolean: true or false.
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] Eric_Lev:
Thank you!

Indeed, the dash charge support is lost with the latest build.

If I am not wrong:

1- From build 20210902, LOS 18.1 for fajita is compatible with firmwares 10 and 11.

2- It is recommended to update the firmware from 10 to 11

via

the official procedure (see this commit, just merged) to keep ANT+ and dash charging support.

EDIT: Successfull update from fw 10 to fw 11 (see screenshot) .... fw 11 is here (if needed ... unzip and follow the official instructions ... use LOS recovery in fastbootD mode).

Thanks @LuK1337 !
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] Saksham03:
We can now update to A11 vendor.

I have updated successfully but, first update to the 2nd September build.

Thanks @LuK1337
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] jabashque:
As @Eric_Lev mentioned, update to the newest build first before updating to Android 11 vendor + fw. Without the kernel changes from the newest build, your phone will end up booting into crashdump mode on Android 11 fw, whether you try booting android or recovery.

I'd suppose if you already did this and your phone enters crashdump upon trying to boot android or recovery, you could still download and boot the latest lineage recovery using the wiki instructions?
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] just4sc:
Shouldn't you reboot to Recovery after step 3 first?
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] jomapp:
Thanks for the great custom rom! Works perfectly.

Only thing that is not working for me seems to be GPS.

Can't get any location.
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] Oblias:
I would say 'Yes'. Makes perfect sense to me.
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] just4sc:
Anyone else with this issue? Was just about to flash this from 17.1 but if there's an issue with the GPS I'll need to wait.
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] jomapp:
GPS started for me to work now, seems like it only takes quite a long time for a gps fix status every time.
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] just4sc:
I installed it and GPS worked but I couldn't get cell signal. I keep getting no service. Had a nandroid backup of 17.1 and tried recovering back to that. Try booting up and got Qualcomm Crashdump. What are my options now? I can get back into TWRP (using 3.4.0.0). Any help is much appreciated.

If I have to use MSM (can I use TWRP?) do I use the TMO stock rom or can I just use the Int'l since I had convert to it prior to the problem?

Also, can I just do a recover from my nandroid backup after getting the stock rom installed or do I need to go through upgrading from 9.0.13 to 10.3.2 then flash 17.1 and then do recovery?

Thanks!

Edit: I got it working by using the All-In_one tool

1) flashed the 10.3 OOS fastboot rom (reboot into system to make sure it's bootable) then back into fastboot mode (PWR+hi vol+low vol)

2) flashed TWRP 3.4.0.0

3) boot into TWRP to flash LOS 17.1

4) flashed TWRP again

5) reboot to recovery and flashed 17.1 again

6) flashed TWRP again

7) reboot to recovery and flashed GApps

8) reboot to system to see if it'll boot up then boot to recovery

9) copied the internal storage files I had saved on the pc back to phone

10) restore nandroid backup but only boot, system image, vendor image, and data)

11) boot to system to check if it'll boot up

12) reboot to recovery

13) flashed GApps again (just to be safe)

14) reboot to system

15) reboot to recovery

16) flashed Magisk 20.4 just to make sure root sticks

17) reboot to system

Everything seems to be back to normal except for one app (Signal - had to uninstall and reinstall and restore Signal's back up data) that keep force closing.

These steps worked for me and there's a bunch of redundant steps but I wanted to be safe and rather perform extra steps than have to redo everything again because of skipping a step. Hope this might help someone else with similar problems.
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] imna357:
Does anyone know how to make the fingerprint faster and accurate just like original OOS, tried all from PIXEN 11, but lineage is far better, but the fingerprint after sometime stops working. Thanks
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] Oblias:
I have no direct experience with this issue, but I have read several posts about this in the 3 Android 11 threads, and they all advise to pick the finger that you prefer most, and register that same finger in about 3 or 4 slots in that settings section. So, instead of registering an index finger on the right hand, then registering an index finger of the left hand, to just use the right index finger, and register that about 3-4 times, and the end result is much improved performance and retention of that fingerprint data.

If you try that, post back with the results, will you?
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] imna357:
Will do, thanks
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] imna357:
I tried registering 5 my right thumb, didn't work still the same, right now just ONE right thumb so far it's working. Hope this will last, I'll report after a couple of days.
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] Michelsup:
Hum. With 27/10 version the screen wakes up again after going to sleep. No time to logcat tho.
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] athulda:
Any issues which I need to be aware of in the rom before making it as my daily driver?
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] anonymous 4 u:
The Cyan Green fod color does make it faster.

Edit: faster than all other color.
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] imna357:
Default is the CYAN and there's no setting to change if in case you need to, it's only available on 10 and OOS, nothing so far on 11 that I know off
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] Dsigman502:
Verizon support added yet???
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] Michelsup:
PowerManagerService: Waking up from Dozing (uid=10201, reason=WAKE_REASON_GESTURE, details=com.android.systemui:BOUNCER_DOZING)...

Found out the phone is going to sleep but without locking as I had no phone locking setup. By registering an unlocking pattern, the issue is gone away.
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] CZG_THEWINNER015:
So, after using this for about a week now. It's really stable. I've only had one bug and one thing that makes my OCD go crazy.

The bug in question is if YouTube is in background play and you open and app that requires a fingerprint the fingerprint scanner doesn't work until YouTube is closed.

The thing that makes my OCD go crazy is when watching a video in landscape and scroll down the status bar the clock is cut off just a little bit. I can't attach a picture cause it says "Bad request".

Another bug to report is clock app plays no sounds for alarm. Do not disturb off. Custom and default sounds don't work.
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] 3316556:
Is there any way to get the original oos apps to work with this rom?

I really like their camera app.
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] athulda:
You could install it using the magisk module

Reference : https://xdaforums.com/oneplus-6/themes/magisk-oneplus6-oos-camera-t3888204
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] OhioYJ:
Is Magisk actually working? I can only get a single specific version to install to LOS 18 and still have it boot. Then no app will recognize root.
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] BeardedGears:
ROM is great but I have to restart my phone at times to clock on things, say in play store I want to install something, clicking on install doesn't register but when I restart and go back in it works then stops working later on ... Can't recall what other apps do it but for sure play store.

How can I do logcat with no root ?
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] BeardedGears:
And I have used updater to update each time, issue has been there for past few updates
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] dwardo:
I just updated vendor to OOS 11 and LOS-18.1 to a self built 20210902 (using TheMuppets).

After successfully rebooting I am experiencing the following issues :

1. Fingerprint scanner is gone... its not even in my settings as illustrated below...

logcat * | grep finger

reveals the following errors :

09-15 03:27:39.245 0 0 I init : starting service 'fingerprint-inscreen-1-0'...
09-02 20:47:01.386 978 978 F DEBUG : Build fingerprint:
'OnePlus/OnePlus6T/OnePlus6T:11/RKQ1.201217.002/2106301531:user/release-keys'
09-02 20:47:01.433 0 0 E init : Control message: Could not find 'vendor.oneplus.fingerprint.extension@1.0::IVendorFingerprintExtensions/default' for ctl.interface_start from pid: 594 (/system/bin/hwservicemanager)
...
09-02 20:49:54.610 0 0 E init : Control message: Could not find 'vendor.oneplus.fingerprint.extension@1.0::IVendorFingerprintExtensions/default' for ctl.interface_start from pid: 594 (/system/bin/hwservicemanager)
09-02 20:49:54.834 1434 5125 V FingerprintService: mDaemon was null, reconnect to fingerprint
09-02 20:49:54.839 1434 5125 V FingerprintService: Fingerprint HAL id: 0
09-02 20:49:54.839 1434 5125 W FingerprintService: Failed to open Fingerprint HAL!
...
09-02 20:50:59.417 0 0 E synaptics,s3320: all finger up
09-02 20:50:59.725 0 0 E init : Control message: Could not find 'vendor.oneplus.fingerprint.extension@1.0::IVendorFingerprintExtensions/default' for ctl.interface_start from pid: 594 (/system/bin/hwservicemanager)
...
09-02 20:54:53.717 594 594 I hwservicemanager: Since vendor.oneplus.fingerprint.extension@1.0::IVendorFingerprintExtensions/default is not registered, trying to start it as a lazy HAL.
09-02 20:54:53.724 0 0 E init : Control message: Could not find 'vendor.oneplus.fingerprint.extension@1.0::IVendorFingerprintExtensions/default' for ctl.interface_start from pid: 594 (/system/bin/hwservicemanager)
09-02 20:54:53.725 594 28248 W libc : Unable to set property "ctl.interface_start" to "vendor.oneplus.fingerprint.extension@1.0::IVendorFingerprintExtensions/default": error code: 0x20

2. Navigation bar is very slow (unresponsive sometimes)... Both in LOS and TWRP

3. Double tap to wake does not work

4. Screen touch seems off i.e. I have to touch a few mm higher than where I should...
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] onliner:
Yeah, it doesn't work even after merging the new kernel changes.
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] jabashque:
Not quite sure what you're facing... I have not encountered any of these issues at all on my own self-builds. (I did run a `mka installclean` just in case before building, since the entire set of proprietary blobs was changed.)
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] hayvan96:
Regarding fingerprint disappearing as an option, I had the same issue on my wife's fajita. It worked correctly for a day or so and then it didn't react at all and after a reboot option was gone forever. And yes I've correctly installed LOS with copy partitions :)

Updating fw (10 series) didn't fix it. Hoping that the 11 upgrade might fix it, even though I'm pessimistic. Reading OP official forums, this happens to people on stock OOS, sometimes restarting in safe mode fixes it, but most of the time it's gone forever according to their feedback.

EDIT: updated fajita to latest build then FW to OOS11 base --> fingerprint is still AWOL
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] dwardo:
Thanks for the feedback

The "just in case" might just be it...

I had the same hunch so last night before going to bed I did a "make clean" and relaunched a build.

This morning I re flashed both OOS 11 and the new "clean" LOS build.

--> Upon reboot everything is back to normal and perfect !
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] hayvan96:
Even fingerprint? Have you applied OOS11 via the payload dumper method or have you flashed the full zip in recovery?
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] dwardo:
Yes everything is fine now even fingerprint :)

Both times (yesterday and this morning) I used the following procedure (used also when upgrading between the various oos 10 subversions in the past)

Reboot to twrp

Install oos 11

Install twrp

Reboot to twrp

Install oos 11

Install twrp

Reboot to twrp

Install los

Install twrp

Reboot to twrp

Install los

Install twrp

Reboot to twrp

Install opengapps

Install Magisk

Reboot to los

I really think the issue was not having done the "make clean" on the first los build I installed yesterday.
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] hayvan96:
And this doesn't cause data loss (avoiding a divorce here lol)? Which version of twrp are you using? Thank you
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] dwardo:
Just never reboot to system while oos is installed on system.

If you do then you will have data loss !!!

Twrp is version 3.5.2_9-0
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] hayvan96:
There's probably a faster way to do the same :

fastboot boot twrp.img

adb shell twrp sideload

adb sideload OOS11

adb reboot bootloader

fastboot boot twrp img

adb shell twrp sideload

adb sideload copy-partitions.zip

adb shel twrp sideload

adb sideload los

adb reboot bootloader

fastboot boot twrp.img

adb shell twrp sideload

adb sideload gapps, magisk

adb reboot

This way, no need to flash twice OOS11 and LOS for A/B partitions, and no need to install TWRP. That's what I did to upgrade my enchilada from 16 to 17.1. But I'll follow your advice, as it worked for you
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] dwardo:
Yes ! But that requires the phone being connected to and you in front of the computer throughout the process :-) !
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] Saksham03:
1. Boot TWRP

2. Flash OOS

3. Flash Lineage

4. Flash TWRP installer

5. Reboot recovery

6. Flash gapps

7. Flash copy partition zip

8. Reboot system
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] BeardedGears:
So had many issues, tried to fresh install of oos and lineage and Google Play can't see usb or external storage so I cannot install apps or upgrade apps...

What's a good way to get things to work ? I'm at a loss ... I may try the steps above and see if that works for me too ...
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] yoruuba2:
Can we officially use OOS11 base?
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] jhedfors:
Yes. If you flash 9/2 first.
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] BeardedGears:
9/2?
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] david72262:
https://download.lineageos.org/fajita flash the build from September 2nd 1st equals 9/2
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] jhedfors:
You have to flash that latest version (9/2) which added compatibility with the OOS Android 11 firmware.
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] yoruuba2:
I'm currently running 09/02.

So if it get it right run OOS11 full zip, and than reinstall 09/02, right?

Thanks
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] jhedfors:
Yes. Flashing both without rebooting between.
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] hayvan96:
You've used this and it works for sure?
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] Saksham03:
It will work
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] BeardedGears:
Wouldn't you Flash twice for both slots
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] hayvan96:
Copy partitions is supposed to do that
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] BeardedGears:
Copy partitions ? There is a option for that ?
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] hayvan96:
You've successfully upgraded OOS10 fw to OOS11 without dataloss? Surprised by the order, specially copypartions at the very end

EDIT : fastbooting to twrp.img lead to qualcomm crashdump mode (OOS1 FW already update via the official wiki).
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] jabashque:
Well, yeah, the prebuilt kernel in that twrp.img doesn't contain the changes to work on R fw without entering crashdump mode. It's less hassle to just follow what the wiki says for updating vendor + fw: https://wiki.lineageos.org/devices/fajita/fw_update
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] ashutosh_13:
Guys where can i download the latest OoS-11 that i need to flash?
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] s.seila:
Oxygen updater.
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] jhedfors:
It is also linked to on this page:

Download: OnePlus 6 and OnePlus 6T receive stable Android 11 with OxygenOS 11 update

OnePlus is rolling out stable OxygenOS 11 based on stable Android 11 for the OnePlus 6 and OnePlus 6T. Head on over for the download links!

www.xda-developers.com
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] ashutosh_13:
Thanks for quick response..I have downloaded it..My current receovery is LOS and i want to install twrp receovery but i am unable to do so.I can see devices using adb devices but its not visible using fastboot devices.Please help
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] hayvan96:
Already did that but fingerprint, which disappeared quickly after having bought this fajita and installed los17. 1,,didn't come back. I was hoping that an alternate method to update the underlying fw would maybe fix it. But anyway, I'll give up
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] ashutosh_13:
I followed the procedure and everything seems to be fine,question is how to vereify that kernel is upgraded or not :)
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] hayvan96:
After two days, I've noticed the display mode (srgb dcpi etc) is never saved, after a lock and unlock, the device is very saturated. It wasn't so saturated before this oos 11 change.
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] vidumec:
Does oos cam work (4k 60fps video) now with new vendor?
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] BeardedGears:
So got it all to work but have a issue where certain apps won't allow me to click on things ie when logging in via Google account, it pops up and you are to select which account, I go to click on one or other and doesn't register ... If I restart and try again it sometimes works
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] BeardedGears:
So the phone works but at times I cannot click on say save for a syslog or in play store cannot click install or update a app
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] BeardedGears:
Log
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] BeardedGears:
Guess my log didn't post 🤣... Anyways anyone run into same issue ?
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] Eric_Lev:
I am also facing this issue.

Note: "hey google" works fine (no root here).
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] kill_master:
Video playback has loads of stuttering.

Anyone else with the same issue?

Tested on YouTube, Plex, Netflix and happened with all of them.

The whole system stutters while playing videos, not just the video itself.
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] thatsnotaclevername:
So does that mean the only workaround is to wait for a new version of twrp.img? Just like hayvan96, I successfully upgraded to the 9/2 build, then upgraded the firmware, and lineage works fine. However, if I try fasbooting to twrp, I get qualcomm crashdump mode.

This isn't a major issue for me since lineage is working fine, I'm just curious if there's any way to use twrp after upgrading the firmware.
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] ashutosh_13:
Guys can someone let me know, How to make sure that my upgrade from old to new vendor firmware and kernel image is successful?
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] Eric_Lev:
Check your baseband version.

.15-00007-SDM845_GEN_PACK-1.417328.2.422944.1 for fw 11.
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] ashutosh_13:
Thanks, I could confirm..
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] jhedfors:
Anyone having camera issues after installing the latest OP11 firmware? Trouble with focus, crashing, switching cameras, etc. Both with stock and gcam.
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] Eric_Lev:
No sweat on my side.

Tip: clean the cache and storage of both cam apps, power off and restart your device.
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] AluminumTank:
Just built LineageOS for microG today and updated. Also updated to OOS11 using the instructions at https://wiki.lineageos.org/devices/fajita/fw_update

So far, everything is working, no issues with fingerprint scanner or camera focus. GCam is crashing though, so I need to figure that out :/

The best thing is that the Verizon RTT issue isn't happening anymore, so no need for the carrierconfig hack :)
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] Sredna76:
There is a place to download lineage with microG prebuilt if you like the easy way and not build it yourself @

lineage.microg.org
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] jhedfors:
Thanks. I tried this, but unfortunately it is still happening for me....

I guess it is time for a factory reset. 😥
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] jhedfors:
I have had no problems installing TWRP while having the OOS11 firmware if installing through the Magisk app, BTW.