Remember position of headers in the outliner

[sergy]

Use case or problem

I can have quite a few headings on one page. I collapse headings in the outline for easier editing. But i cant do it

Steps to reproduce

1. Collapse headers in outliner
2. Do any operation with a heading in the text like delete or add a part of a heading or create a new one

Expected result

Headers in the outliner will remain collapsed

Actual result

In any action, they unrolled

Proposed solution

make the position memorable