In the UI Enhancement thread on the dev mailing list Brian J suggested "links to jump to a certain category" to improve navigation on the "Available Plugins" tab of the update center (Source)

Other suggested options were

• "search mechanism" (which could be implemented nevertheless)
• "a second set of tabs by category"

The attached screenshot shows a table of contents for all categories of the "Available Plugins" tab in the sidepanel.

Before opening a pull request I'd like to know

• is the sidepanel the right place for the TOC?
• should it be always visible while scrolling?