14.3 Mail.app - Corrupted/Garbled Text When Composing Messages

Thank you for taking the time to document this issue with Apple support. I have taken several steps on my own that seem to have minimized the issue I reported on Jan. 26.

1. I started using Outlook, with no changes to my system. Outlook editing worked as it should with no issues, whereas Apple Mail continued to do its corrupted/garbled text when editing.
2. I changed my settings for keyboard to NOT show inline predictive text. That did not help with the corrupted text display in Apple Mail editing.
3. In Apple Mail, I did mailbox rebuild. When that was occurring my antivirus program identified and quarantined some attachment in the ~/Library/Mail/ ... inbox.mbox path. When the rebuild was finished, I did a full system scan, and the AV found 2 more infected attachments. These were likely in unopened junk mail that got downloaded from the Exchange server during the mailbox rebuild.
4. I did system maintenance with OnyX, which does a number of things, including the rebuilding of the apps launch database, clearing caches, etc.
5. Then I used the new Apple Diagnostics program to test all the hardware systems in the new M3 Pro. The diagnostics passed with no detected issues: Use Apple Diagnostics to test your Mac - Apple Support
6. I did a complete re-installation of MacOS 14.3 via the Mac Recovery mode.
7. I restarted, then I did a complete AV scan again, and no malware was detected.
8. I have been working normally since Jan. 26 with many apps with no issues. I decided to try Apple Mail once again, and so far so good. But I have not been writing long messages with significant editing, as I was doing when the corrupted text display issue first reared its ugly head.

I did these steps because, occasionally in the past, I was able to resolve issues following MacOS upgrades that were apparently caused by some old prefs/caches leftover from past OS's and apps.

Seeing this on my M3 Max. The bug behaves like the issue is related to the predictive text, but it does appear to be a "display-only" issue. For example, if I cut the garbled text and paste it back in, then it displays correctly.

Perhaps worth noting that I only ever compose messages in plain text, but I'm not sure if that matters for the bug.

To avoid having to resize the window a fix as you type work around seems to be can just add a space (or any character) at the start of the messed up paragraph (or paragraph above) to force a reformat of the paragraph which usually clears the garbled bits, then just take the added space (or other character) away again and (usually) are left with correct text correctly formatted - although if you then keep typing further the issue will probably come back (probably differently) and require further adding and removing of spaces/characters. fingers cross Apple release a fix for this in next update of Sonoma.

The workaround I've been using in Mail: Once the bug rears its ugly head I save the message as a draft and close it. Then I open the draft back up and continue working on the message. That fixes it... at least until it starts happening again. Rinse and repeat.

Mac Studio, M1 Max

I would like to suggest that there is no point in posting more "me too" messages. We should concentrate on getting a consensus on how to cope with it until Apple fixes the bug. Scanning through the previous messages, everyone seems to agree that it's a problem with the display, not the underlying text, so all that is needed is a way to force a refresh, either by:

1. resizing the window.
2. selecting all the text with ⌘-A (you may need to deselect it before it corrects itself completely).
3. just typing on until it clears itself, although that can be hard when you are typing through mangled text.

All three have worked for me. Please could people confirm whether one or more of these solutions work for them as well.

Yesterday afternoon upgraded to 14.3.1 and so far the problem appears to be fixed.

FYI update: did original troubleshooting mentioned in prior posts with Apple support, reinstalled the OS per Apple support, then my case number was escalated to a team lead in Apple support. After steps listed below, the lead is escalating the issue further to engineering with a full data capture of my system and a screen recording of the garbled text happening in real time on my computer.

I highly recommend that everyone do the same thing so engineering has escalated case numbers for this issue on intel, M1, M2, M3 and laptop and desktop hardware systems.

On the call with the support lead, we did the following:

1. Support person saw the issue happen in real time
2. We did a screen recording of the issue happening again in real time
3. The lead sent me an email on how to send files to Apple, and walked me through all the steps
4. That email asks the user to download a Capture Data app
5. A permission for full disk access was given to the Capture Data app
6. The app had a function to pull a full system log, which output a 500meg file
7. The system log and the screen recording were then attached and sent to the customer support lead
8. The customer support lead is sending the log and recording to engineering with all related info
9. in 24-48 hours someone from engineering (I believe) will get back with further information or steps to do

Once again, I recommend everyone do the same thing so engineering can get more and more of these escalated case numbers with the accompanying system reports and screen recordings of the issue.

I see today February 8 apple released iOS 17.3.1 with a text fix. So I checked my Mac and it also has a fix in 14.3.1 out now. So happy for this and hope it fixes this problem we have all been struggling with.

FYI everyone - if you want apple to fix this, call support, create a case ID and go through troubleshooting steps with them. They CANNOT REPORT the issue to engineering until ALL troubleshooting steps are exhausted. The last step includes re-installing the OS, and only after that fails to work is the issue reported to engineering as a problem they need to solve.

If you wait for others to do the above, you're just making it take longer for a fix to happen.

Apple support tried the following with me:

1. recreate the issue by composing an email
2. verify issue is limited to composing only (an email with issue, when sent, is not received displaying the issue)
3. create new user account > add email user (with email you use) > recreate the issue there

Once the issue happens with a newly created user, it's identified as a systemwide OS problem.

Once an OS reinstall does not fix it, the customer service rep will refer it to engineering to be fixed.

Once you go through steps 1, 2, 3 (or more) above, you'll be sent an email on how to reinstall the OS.

I'm getting this bug under Sonoma 14.3, on both a iMac, Retina 5K, 27-inch, 2020, 3.6 GHz 10-Core Intel Core i9 and a MacBook Air, 15-inch, M2, 2023. I did not have it before Sonoma 14.3.

My temporary workaround if it text display glitches when I need to review what I've written is to grab the window and resize it to force an "accurate" rewrap. That usually clears it up. Looking forward to the update that fixes this!

I'm getting the same garbled text and weird blank areas in the mail app on both Intel iMac and Apple Silicon Macbook Air - both just upgraded to 14.3 (sadly). It happens just as I'm typing along, and PRESTO, all of a sudden, the rendering of the text becomes garbled. If I highlight the text, change the font size, it renders back to the correct appearance. APPLE - FIX THIS PLEASE - it's driving me nuts. Example below.

That's strange. Turning off inline predictive text resolved the problem for me immediately. I am now writing long e-mails in Mail without any glitches.

Turning off inline predictions in keyboard settings seems to have solved this issue for me.

This obviously needs fixing asap, but in my limited testing just now, I just needed to type ⌘-A (i.e., Select All) for the original text to be displayed again, allowing me to continue typing.