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

Upgrade to MacOS 14.3.1.

It should fix the problem, which was in WebKit. The software update explicitly says it is a fix to this erratic display problem when editing. In addition to Apple Mail, this was occurring in other apps that use WebKit.

It's a bit scary to see something like this with a brand new computer, and wonder if something is wrong with the new M3 Pro Apple Silicon hardware. I certainly did, until I saw in this forum that it was happening to many different computers, including ones with Intel processors.

This display issue when editing is a documented software bug that 14.3.1 should fix.

It now appears that Apple has addressed this problem in MacOS 14.3.1, just released yesterday (2/8/2024). Updates are also available for iOS 17.3.1, iPadOS 17.3.1, watchOS 10.3.1. Specifically, this problem was mentioned in the updates: "includes a fix for a bug that could cause text to unexpectedly duplicate or overlap while typing".

I've updated my OS's, and thus far have not been able to replicate the problem, even with inline predictive text turned back on in keyboard settings. Other sources indicated that the problem was in WebKit: https://tidbits.com/2024/02/07/macos-14-3-sonoma-text-display-bug-to-be-fixed-soon/.

Thank you, Apple for fixing this annoying bug!

Sonoma 14.3.1, released today, contains a bug fix for: "Text may unexpectedly duplicate or overlap while typing". About time!

I've responded twice earlier to this issue. I'm using a new M3 Pro, Nov. 2023.

I had initially concluded that the garbled text sometimes occurs during the dynamic rendering of the message being composed when using Apple Mail on the MacOS 14.3. As others have discovered, doing something that causes a redraw of the message content seems to restore it, so further editing can be done. The tactic that usually works is grabbing a corner of the message container and resizing it to force a redraw.

New observation: the garbling is more likely to occur when both text and graphics are being rendered within the message being edited. E.g., when an icon appears such as for an attached PDF or .docx file. Also, sometimes when a hyperlink (URL) is embedded within the message, Apple Mail may generate a thumbnail icon of the webpage that the URL points to. And, if the inline text prediction feature is enabled, that may also interact with the rendering process.

In all these cases, this happens to me when a mix of text characters and graphics are being dynamically represented in longer text messages. When I compose longer messages that do NOT contain any URLs or attachments (i.e., no images being rendered), with inline text prediction disabled, the garbled/corrupted text bug does not rear its ugly head--in my experience.

Apple, please fix annoying bug ASAP! It makes Apple Mail unpredictable and unusable! Ugh.

I posted this once before here, but I think most of you missed it. I found the easiest possible workaround. The problem is still serious, and I would be furious if I have to continue constantly doing this workaround for months or even weeks, but here it is:

Thanks to reading the many good comments regarding this problem, I realize that what you type IS still there, even though when it glitches, you might not be able to see it. So all you do is simply toggle from your composing window to the Mail window and back using command-tilde, and you'll be good to go. Your text will go back to looking like it's supposed to look! This takes 1 second and works 9 times out of 10. 1 time out of 10, you might have to toggle back and forth twice.

I have been experiencing a similar, but slightly different issue. For me, I will be editing an email and a sentence that I just wrote/edited would be replaced by a previous sentence that I wrote above. E.g.:

Hello XXX,

Here's the first sentence of my email.

Here's the second sentence of my email.

Best,

XXX

Would get changed to...

Hello XXX,

Here's the first sentence of my email.

Here's the first sentence of my email.

Best,

XXX

If I save the draft, close the message, then open it again, my original, intended text is there. So, it seems to be a display issue more than an actual over-writing/composition glitch.

This problem on my MacBook Air Apple M1 2020 with OS 14.3 is maddening. I'm composing my emails in TextEdit because I can't stand the constant interruption of resizing the window. But thanks to all the good comments under here under this question, I now realize that what you type IS there, but it just may not be displaying correctly. So my new workaround is to simply command-tilde (~) from the email I'm composing to the main Mail window and command-tilde again back to my composing. Try it!

It's disappointing Apple didn't discover this error, which took me about 5 minutes to find. I compose in Mail all day, so this is a very frustrating problem. The screen shots in this thread are good.

Hitting undo just messes you up more. It's really making me nervous and now I have to re-read every email twice before I send it.

I've encountered the same problem (just updated to Sonoma 14.3 last night). Turning off "Show inline predictive text" in System Settings seems to resolve the issue.

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.

I believe this was fixed in macOS 14.3.1. From the release notes:

This update provides bug fixes for your Mac including:
- Text may unexpectedly duplicate or overlap while typing

Yes, I am experiencing this very annoying problem when editing in Apple Mail. I have a new M3 Pro running the latest MacOS Sonoma 14.3. This had not occurred before the OS upgrade, a few days ago. I was worried that something was wrong with the M3 Pro hardware. However, I see other posts here that indicate the problem is not isolated to Apple Silicon, and seems to have surfaced right after the upgrade to MacOS 14.3.

And it seems to be isolated to Apple Mail so far. It makes it nearly impossible to compose longer e-mail messages. I may have to switch to another Mail app until Apple fixes this really bad bug.

Yes, it's in the display part of the code. I've found that I can force a redisplay to remove the garbled overwritten text by using the Mail Format tab, and then selecting either rich text or plain text, which forces a screen refresh to show all the typing I thought was lost. Otherwise, I can't see the text I'm typing!

It's actually horrible, making Apple mail message editing unusable. I'm ready to switch to MS Outlook to see if that helps.

Come on Apple! This is completely unacceptable. Fix the problem!

At the moment the only way to get around this problem is to resize the window a little bit when this phenomenon occurs. This forces a redraw on the screen and things get corrected. This of course only works an a Mac, not on an iPhone. Apple has to fix this fast. Very fast.

The quickest workaround I've found is to resize the email message window - click on a corner of the email window and give it a quick jiggle with the mouse or trackpad.

Same here - very annoying, and I hope short-lived.

Ad-hoc cure: undo followed by redo usually corrects the glitch (with a stable result at that point). So it's just a matter of typing cmd-z followed by shift-cmd-z, which is quick, but it has do be done all the time while the problem persists in principle.