I use footnotes and comments extensively. I’m also an avid keyboard shortcut user. One thing I think Scrivener desperately needs is the ability to jump directly from Editor text that is formatted as a footnote or comment to the associated footnote or comment in the Inspector, with the cursor being moved from the Editor to that specific footnote/comment in the Inspector. As it is right now, I have to reach for my mouse, click on a footnote/comment in the Editor to reveal the footnote/comment in the Inspector, and then double-click into that footnote/comment to edit it.
I picture the shortcut working similar to how the Escape key does when you are editing a footnote/comment in the Inspector: in that case, pressing Escape moves the cursor from the footnote/comment back to the associated text in the Editor, which is very convenient. My suggestion is to give us the reverse option as well: let us jump from the footnoted/commented text in the Editor directly inside the associated footnote/comment.