ProseMirror (and as the sibling comment mention, Lexical) should handle this fine.
Both mobile Safari and Chrome Android do a ton of weird things that their desktop siblings don't, and play loose and fast with standards, so getting things to work correctly there tends to involve a long tail of hacks. Wordgard will get there but the focus before this first release has been on architecture.
Yeah I did a review of web based rich text editors a couple years ago. They all seemed fine on desktop, but on mobile every one I tried was junk. I couldn’t select. Autocorrect was broken. Tapping text didn’t move the cursor. Typing would stop working. The keyboard wouldn’t disappear when the element lost focus. And so on.
There have been several efforts over the last couple decades to add a proper rich text element to the web. I don’t know why they have all failed - I guess it’s a large, complex and thankless task. It’s a pity. Proper native rich text support is one of the web’s big blind spots. It’s a problem native platforms have solved decades ago.
Meta has a text editor framework called Lexical that works well on mobile, I've used it at work before with great success. Perhaps you missed this one?
That's the ideal solution, because (it seems to me that) the issues that break rich text editors are caused by non-interoperable ad-hoc hacks from mobile browsers and operating systems. These rich text editors can work perfectly fine on desktop browsers, yet have countless buggy behavior on mobile. The editor side is not the main problem, it's the mobile side that needs to be fixed and better implemented in a consistent manner across platforms.
I disagree. Rich text editors on the web are already a massive hack, because there aren’t any built in input elements which support rich text. There’s just contentEditable and textarea (plain text). There’s no such thing as “doing it properly” when it comes to rich text. Editors have to hack around what the browser provides via a million event handlers. And - surprise! Mobile browsers don’t expose the same events as desktop browsers.
The right fix is for browsers to have a real rich text element of some sort. Then editors wouldn’t need all their hacks. And mobile browsers would be able to behave correctly when you tap on some editable rich text.
Wordgard failed that test. Inputs coming from autocorrect or the keyboard suggestions are swallowed and delete the partially typed/misspelled word.