Macbook in-built display shows closed applications translucently

macusersg wrote:

I updgraded my Macbook pro to Big Sur (11.5.2) a couple of weeks back. I don't know if that's what caused this issue, since last week the in-built display (external display is fine) has become translucent and shows apps that I have already closed. As you can see in the attached photo, I have the Terminal app open but I can still see a Safari window of the Wikipedia homepage as well other apps I had already closed.

Apple Support suggested booting in Safe Mode, Resetting NVRAM and Resetting SMC - none of this resolved the issue.

It looks to me like a software issue and the display's memory has probably not been flushed out completely when switching windows or closing apps. Any advice on how I can fix this? Thanks.

https://discussions.apple.com/content/attachment/dcf1c652-cfde-42a3-b098-efdd5e17edd6

It almost looks to me like your Terminal window is occupying all of your screen real estate...?

Can you make that window smaller or quit the Terminal app?

It appears you have many tabs open in the Terminal...

You can always try a safeboot to clear system caches if this is a one off anomaly

Try a SafeBoot https://support.apple.com/en-us/HT201262

Takes noticeable longer to get to the login screen, does a 5 minute disk repair before it fully boots up, and certain system caches get cleared and rebuilt, including dynamic loader cache, etc.

Login and test. Reboot as normal and test. Caches get rebuilt automatically.

To sort anomalies like yours I would simply try reinstalling the macOS on top of your existing macOS and test.

How to reinstall macOS from macOS Recovery - https://support.apple.com/en-us/HT204904

If you choice wisely here your user data remains untouch, however it is always recommended to have a current backup.

macusersg wrote:

To sort anomalies like yours I would simply try reinstalling the macOS on top of your existing macOS and test.

How do I reinstall without risking losing my data? Also, is there an easier way to do this? Would downgrading from 11.5.2 to 11.5.1 have the same effect?

Thank you.

You are always at risk of losing your data—this is why backups are recommended if you value your user data.

Did you read the Recovery options...

When you upgrade your macOS do you typically loses your data(?)— no, not by design.

When you reinstall the macOS on top of (Compared to erase and reinstall) your existing macOS, is just that. It reinstalls a fresh copy of the macOS leaving your user data undisturbed.

Options are given above— try a safe boot

If somehow you are weak in the knees and can not get your head around Recovery, You can get a good look at your System config. and reveal conflicts or issues, you can download/run this trusted utility https://etrecheck.com  

If you need help interpreting the report you can post it here in its entirety in the "Additional Text" box in the editing toolbar below, in your reply.

I suspect the direct route is simply re-install the macOS.