If the bookmark star is blue, it means the web link is stored somewhere. Try searching for the link.

Try unbookmarking all the pages that you had previously bookmarked. Refresh the page and bookmark the selected pages again. I hope that works.

I'm not sure what you mean. Where can I search for the link?

Also, I can't actually remember what all of my bookmarks are so I need a list to choose from, I can't search for each of the bookmarks that have disappeared as I can't remember what they all are.

I've tried your suggestion NehaGoyal, but it still isn't showing in my list of bookmarks even though it's telling me it's bookmarked.

It depends on how you add the bookmark.

If you create the bookmark by clicking the star, Firefox auto-adds the bookmark to the Unsorted Bookmarks collection. If you click it again, that likely will be highlighted in the dialog.

Unsorted Bookmarks is not listed on the Bookmarks menu displayed from the toolbar button. It is available using these other views:

• (classic menu bar) Bookmarks menu
  • if you do not normally display the classic menu bar, you can display it temporarily by tapping either the Alt key or the F10 key

• Bookmarks Sidebar
  • Ctrl+b (assuming the page doesn't intercept it)
  • Bookmarks menu button on the toolbar > View Bookmarks Sidebar

• Library dialog
  • Ctrl+Shift+b
  • Bookmarks menu button on the toolbar > Show All Bookmarks

If you want new bookmarks to be added directly to the Bookmarks Menu, these other methods will do that:

• press Ctrl+d
• right-click a blank area of the page > click the star icon on the top row
• (classic menu bar) Bookmarks > Bookmark This Page

I sort my bookmarks in to appropriate folders and move them from the unsorted bookmarks once bookmarked, and I could see them previous to turning the computer on today. They've just disappeared.

I've tried to search for the missing bookmarks using the three ways you list above, and using the bookmark sidebar does show some of the bookmarks missing from the library dialog, but I am still missing bookmarks from the sidebar.

Hmm, I hope this doesn't indicate that your places.sqlite database -- the file that stores bookmarks and history together -- has become corrupted, although that sometimes happens.

Could you try using an export of your bookmarks as a tool to locate the missing bookmarks? You can export your bookmarks to an HTML format file, open the HTML format file as a web page in Firefox (in a tab) and then use Find (Ctrl+f) within the page to discover the current location of a bookmark or folder by title.

See: Export Firefox bookmarks to an HTML file to back up or transfer bookmarks

The layout is "flat" so it's hard to see the "nesting" of folders, and you have to hover the titles to see the URLs. To address that, you can "hack" the appearance of the page as follows:

(A) Select this entire script and right-click > Copy it:

var s = document.createElement("style"); s.setAttribute("type", "text/css"); var t = 'dl > dt > dl { margin-left: 2em; } a[href] { text-decoration: none !important; display: inline-block; margin-bottom: 0.25em; } a[href^="javascript:"]::after { content: " (bookmarklet)"; font-style: italic; color: #000; } a:not([href^="javascript:"])::after, a[href^="file"]::after { content: " (" attr(href) ")"; font-family: sans-serif; color: #000; }'; s.appendChild(document.createTextNode(t)); document.body.appendChild(s);

(B) In the tab with the exported bookmark document displayed, open Firefox's Web Console in the lower part of the tab using either Ctrl+Shift+k or the Developer menu.

(C) Click next to the caret (>>) at the bottom of the Web Console and paste the script (Ctrl+v or right-click > Paste) and then press Enter to run it.

If it worked, you will see the page addresses show up in black text next to the blue page titles, nesting of folder contents, and slightly more vertical spacing.

You can close the web console now, there is a small "x" on the right end of the bar listing Inspector, Console, etc., or the keyboard shortcut Ctrl+Shift+i might do it.