Pasting paragraphs sometimes adds unexpected linebreaks

[mejo-]

Describe the bug
When pasting paragraphs to a document, sometimes unexpected linebreaks are added in between the paragraph. As soon as you do one change in the paragraph, all unexpected linebreaks get deleted at once.

As an example, paste the first 3-4 paragraphs of the wikipedia article about Fairy Tales into a document.

To Reproduce
Steps to reproduce the behavior:

1. Open a document, paste the example paragraph from above.
2. See unexpected linebreaks
3. Add one character anywhere in the paragraph
4. The the unexpected linebreaks disappearing.

[juliusknorr]

This seems to come from the white-space: pre-wrap; that is added to the paragraph. Might be coming from @tiptap/vue-2/src/NodeViewContent.ts

[mejo-]

Indeed, that's the reason for this behaviour. I wonder whether we should use our own implementation of NodeViewContent without white-space: pre-wrap? @juliushaertl and @max-nextcloud do you see any reason why we would need white-space: pre-wrap in NodeViewContent?

[juliusknorr]

This seems to come from the prosemirror stylesheet recommentations ad would also warn in ProseMirror/prosemirror-view@b8b814c, but i think it the original paragraph node doesn't have it we can also drop it here.

ProseMirror/prosemirror#981 might give a bit of reasoning for what it is needed