Custom Sidebar Extension

Hi, first of all, thanks for this great project! I could not find a discussion dedicated to this exact idea/feature so I am starting one here. Feature Description It would be great if there was a way to add new modules/components to the sidebar using extensions. Currently, the main purpose of the sidebar is to expose additional context/view-specific metadata and tooling (e.g. revisions, comments, shares in the details view). Additionally, there is also a sticky section at the bottom (currently only contains the activity log) that shows the same elements regardless of the current context/view. I believe it would be great if an extension could add custom modules/components to both of these sections (1. contextual section, 2. sticky section). . The custom compone…