- The default behavior that triple-click to selects a whole paragraph/line will stop at the first contenteditable=false element.
- Android may dismiss the keyboard & selection if the selection ever touches one of your contenteditable=false marker elements.
- Firefox won't let you place the caret in between two contenteditable=false elements, or at the start or end of a contenteditable=true element if the first/last child is contenteditable=false.
Why not use ProseMirror?
Why not use ProseMirror? It doesn't fix this issue, does it? At least in the demos on their website you cannot insert text at the beginning of a styled element. You cannot do it even in a native application (at least on macOS) without a custom handling of the selection.