Make sidebar navigation more intuitive

[pedroms]

Describe the bug
I don't consider this a feature request, but more of a “UX bug” (doesn't match expectations).

The sidebar navigation (video effects, cursor, webcam, and captions) is not intuitive. Especially because it's hard to notice, as it's visually detached from the element it controls (the sidebar itself).

Expected behavior
Some non-exclusive ideas:

• Move this navigation to be tabs at the top of the sidebar.
• Merge all controls into a single scrollable sidebar. The navigation then acts as a “table of contents”, that the user can use to locate themselves in the editing sidebar, and click to jump to a section of the sidebar.
• Turn the navigation into an accordion, where the user clicks sections to open/close them (like in VS Code).

Screenshots

Desktop (please complete the following information):

• OS: macOS