[marijn]

> don't the coordinates of the cursor position depend on the rendering of the text which is under the browser's control?

Yes, but you can ask the browser (using `getBoundingClientRect` and `getClientRects`, which also exist for text range object on all halfway modern browsers.) Or you can insert the caret element inline at the correct place.

What would be hard about showing a selection from another person?

[rocketraman]

Not "hard" as such. Just requires a completely separate code path than the local cursor and selection machinery. That isn't too much of a barrier though... I look forward to its implementation in Prosemirror!