Multiple lines delete issue

I’m working with Remirror and I have a multiple line (simultaneously) editor, I just realized there’s an issue when deleting the content of a line and then pressing backspace again, it is selecting the whole content of the previous line and pressing backspace deletes all the text. This issue exists in prosemirror, you can find a simple example to reproduce the issue here.

It is important to mention that it has nothing to do with the subject element in contentExpresion, the issue is still reproducible by replacing that with paragraph{2}

It does have everything to do with the content expression though. If you require at least two blocks at the top level, the editor can’t let you join those blocks, since that would violate the schema. Use "subject paragraph*" and the problem goes away.