If I follow you, I think this is unfortunately a limitation of ProseMirror witch is the underling library TipTap is built on. From memory they haven’t completed

If I follow you, I think this is unfortunately a limitation of ProseMirror witch is the underling library TipTap is built on. From memory they haven’t completed it due to issues with how browsers handle text cursors in online nodes. It’s a year since I last tried something similar and I think I ended up layering elements on top of where I wanted them from outside the editable element in combination with marks. Don’t take my word for it though as a little out of practice with TipTap, it and ProseMirror are awesome though!