Under Firefox, CTRL+SHIFT+B brings up the bookmarks manager (which, oddly enough, has the window title "Library"). The structure of the Bookmark Manager is very, very much like File Explorer.
If you don't happen to open with it in the "From Internet Explorer" list of bookmarks, then Shift+Tab back over to the tree view, get yourself to that group, then tab back over in to the actual bookmarks list for that group. Locate the bookmark for the page you need to edit. Since I have no idea what you've called it or how it's stored I can't get more specific about what to search for. Once you've landed on it, you can then hit Tab and start moving through the edit boxes for a bookmark:
Brian - Windows 10 Home, 64-Bit, Version 1809, Build 17763
Explanations exist; they have existed for all time; there is always a well-known solution to every human problem — neat, plausible, and wrong.
~ H.L. Mencken, AKA The Sage of Baltimore