Requirement description：
When watching videos and reading articles, taking notes often needs to jump under different title levels in my writing notepage, but there are many lines resulted not to quickly find the previously titles of outline. Therefore, a quick call out subwindow of Outline Title Preview on the writing line is needed to facilitate the adjustment of the outline title level of the current writing line.
Some screenshots：
- design of call out window of Outline Title Preview
2.when change outline level of writing line, Outline Title Preview would autochange depend on the level
thanks a lot