Using Firefox, I moved the bookmarks toolbar to the menu bar.

To do this, make sure you have the bookmarks toolbar visible. Right-click on the menu bar or around the location box, then select 'customise'. Drag 'Bookmark toolbar items' to the white box next to the help menu. You can now hide the bookmark toolbar again.

Now if you add a bookmark to the bookmark toolbar, it appears on the menu bar. You can also drag bookmarklets on to it.

I have been doing it this way for years. Of course, there is less space on the menu bar, so you can't have as many bookmaarks as on a toolbar.