**Steps to replicate the issue** (include links if applicable):
* Go to [[ https://en.wikipedia.org/wiki/User:EnronEvolved/sandbox#Order | this section of my sandbox ]].
* Edit the source of the section.
* Place the cursor in any position other than the first on the final line (beginning with `<!--This-->`). Step can be accomplished using either the mouse or the arrow keys.
**What happens?**:
The cursor's position becomes disjoint from where text is inserted into the article. For example, in the string `Foo|bar` (`|` representing the apparent cursor position), pressing `l` results in `Foob|lar`.
Inserting an additional character at the end of the previous line results in desired behaviour.
**What should have happened instead?**:
`Fool|bar`
**Other information** (browser name/version, screenshots, etc.):
I'm running Firefox 127.0-mint-001 on Linux Mint.
I think that this bug might be caused by incorrect whitespace wrapping, as there seems to be an undelete-able leading space on the offending line, which vanishes if you try to insert a character before it.
Could this issue have the same underlying cause as T360351 and T355625?