I found this while writing Creating a link that comes after a square bracket confuses the editor.
It looks like the editor's "Insert link" doesn't like trying to link text on a new line where the first character is a square bracket. I'll have to use a screenshot to explain
[this makes autolinker unhappy
results in this highlighting and no link pop up in the editor:
Clicking "Insert link" again works, and captures the selected text and the empty bracket as per the previous bug I found.