I reported earlier today that I had an "Other bookmarks" folder that somehow had gotten my last twenty bookmarks added to it when I really wanted them in the main bookmarks folder. Here's how to fix that accessibly.
1. Open Firefox.
2. Open the Library page with Control plus Shift plus B. Although it contains bookmarks, among other things, this is not the same as the Alt plus B Bookmarks menu.
3. Press TAB twice to get to the Library tree view. This includes things like downloads, history, and bookmarks. Since Bookmarks is the last Level 1 branch, the best thing to do is press the End key to get to the end of the list of bookmark folders, all of which are Level 2 branches off the "Bookmarks menu" brandh.
4. Move up the list with the up-arrow key until you find a folder with bookmarks in it that you want to move elsewhere, and press TAB.
5. Select the bookmark(s) you want to move in the usual manner, either by holding down the Shift key and pressing down-arrow, or by holding down the Control key, pressing down-arrow, and then pressing space bar for each bookmark you want to select for the move operation.
6. Press Control plus X to cut the selected bookmarks to the Windows clipboard.
7. Press Shift plus TAB to move back to the Library folders tree view.
8. Find the folder into which you want to paste the previously selected and cut bookmarks. If you want them to appear in the main bookmarks folder, select the item in the library list called "Bookmarks menu," level 1 in the tree view. Note that you do not need to open this or any other branch of the Library/Bookmarks tree view in order to paste something into it.
9. Press Control plus V to paste thecontents of the Windows Clipboard which, unless you've changed it, contains the bookmarks selected and cut in steps 5 and 6 above.
10. Close the Library tree view by pressing Alt plus F4.
The bookmarks which you pasted are now at the end of the master bookmarks list.
Now that you've added some misplaced bookmarks to the end of what may have previously been a nicely sorted list, you can sort the list by opening the Library tree view with Control plus Shift plus B, pressing TAB, navigating to the Level 1 branch called "Bookmarks menu," pressing the Application key and selecting Sort.
Hope this helps.