This isn’t specifically about ProseMirror, but I encountered it in a ProseMirror-based editor and thought someone here might have an insight.
Firefox seems to lose track of the cursor’s column position when moving between elements styled with display: flex
.
In this demo (a standard contenteditable div, containing flexbox sections), the cursor will jump to the end of the line when moving up and down between paragraphs in Firefox, but not in Chrome.
I haven’t yet found a report of this issue, or a suggested workaround.