Yeah, that trying to bold half of a sentence - or even better, the middle of a sentence - is why i was wondering about simpler alternatives to DOM. Some time ago i toyed around with an HTML editor[0] (that one had to use a DOM anyway, but my question is for rich text editing in general - BTW the rectangles in the shot show a selection that goes across nodes) and doing something like that involved traversing all the nodes (going both down and up the node tree, starting from the cursor's starting position), finding the closest common ancestors under the selection, creating "B" siblings to them and then reparenting them under these new "B" nodes.

You can move a lot of that stuff to reusable methods but personally i find the whole "editing" aspect to be more involved than the "drawing" side - and also the one more likely to be different than a plain text editor - when dealing with DOM-like structures. Hence why i am interested to see what alternatives there are.

[0] https://i.imgur.com/jLlyNSS.png