The user can select what happens with a bookamrk after it expires. New
option allow bookmark's reminder to be kept even after it has expired.
After a bookmark's reminder notification is created, the reminder date
will be highlighted in red until the user resets the reminder date.
User can do that using the new Clear Reminder button from the dropdown.
Users can now pin bookmarks from their bookmark list. This will anchor the bookmark to the top of the list, and show a pin icon next to it. This also applies in the nav bookmarks panel. If there are multiple pinned bookmarks they sort by last updated order.
* Remove unneeded bookmark name index.
* Change bookmark search query to use post_search_data. This allows searching on topic title and post content
* Tweak the style/layout of the bookmark list so the search looks better and the whole page fits better on mobile.
