That's a dumb solution.

@Greg: You're dumb.

Thanks for your replies. I'm looking for a way to just right-click on the tag in the Library and delete it. The command is already in the context menu, but it's not working because nothing happens when I click on it.
I can just delete the unwanted tags from each bookmark, but that Delete function for tags is there precisely because deleting tags from bookmarks one by one is tedious when one has many bookmarks. So my questions are:
-Does anyone know why it isn't working (conflict in my config, bug, command not implemented)?
-Is there another way of getting the same thing done quickly (i.e., without removing the tag from each bookmark that has it)?

I wasn't being silly. Click the tag in the left pane so all its associated bookmarks show up in the right pane. Ctrl+A in the right pane to select all the bookmarks, then Delete to delete them. The tag is then automatically deleted. This is exactly the same thing as "removing the tag from each bookmark that has it." You are not really deleting bookmarks this way, only the association between bookmarks and their tag. Try it.

Hi, I tried deedee's solution and unfortunately it does not work for me. Has anyone else had any success deleting tags? Or does anyone have a viable workaround until an extension has been created and this feature had been implemented in the next update of FF3?

Thanks for the link Isid. There seems to be a few workarounds there which do work but it's definitely not an ideal situation. But at least it deleted the tags that I wanted removed.
Also, reading that bug report, it seems that deedee's solution is a bit hit and miss...it works for some and not for others. I guess I am one of those unlucky others.
Thing that I'm going to hold off adding tags to my bookmarks until a more stable and robust system has been released...cos I would not want to re-tag everything if something goes wrong.

hi

i have a similar problem and made one obersevation - there are "hidden bookmarks"

1) Tagging/ Organizing Bookmarks for the first time...
- tagged existing bookmarks with tagshifter migration tool
- decided afterwards to delete some of the tags
- decided afterwards to delete some of the tagged bookmarks

2) Wanted to delete some tags afterwards....
- could delete some tags completeley (by marking all bookmarks that were shown for the tag and deleting them all - the tag vanished afterwards)
- could not delet some other tags also i used the same procedure (deleted all bookmarks but tag does not vanish

My observation
- if i look at these remaining/undeleteable tags with the tag shifter sidebar there are bookmarks shown (which are not shown in "organize bookmarks")
- some of them are rss-feeds, some of them are websites - these are exactly the bookmarks which I decided to delete in step 1

Hope there will be a solution soon... will wait some time and maybe try a workaround...

"You are not really deleting bookmarks this way, only the association between bookmarks and their tag. "

And that's why its stupid. Totally counter intuitive and confusing to non nerds.

This was making me crazy also. I'm pretty sure I just fixed it, but it's a little tricky.

First, locate your profile folder and back it up (I just copied mine to the desktop), next install this add-on: https://addons.mozilla.org/en-US/firefox/addon/5817

We'll be editing some entries in the DB file places.sqlite, and that add-on will allow us to make those edits.

Once you install the add-on, browse to the places.sqlite file in your "real" profile folder, that's what we'll edit. Next, go to the table moz_bookmarks, which contains all your bookmarks, folders, tags, etc. You can write out your own SQL or use the "Search" button near the top of the "Browse & Search" tab on the right pane, and look for all those entries where parent = 4. This is the value given to tags. You should then see a unique row for each of your tags, including a bunch with blank values under title if you tried to manually erase the tags before like I did. Then simply select the bad tags and hit the "Delete Selected" button. I restarted firefox just in case, but the changes may show up without, I'm not sure.

I have no idea if this "voids your warranty" so to speak, so use at your own risk, but everything seems normal to me so far!

I took the cowards way out and just reinstalled FF. Screw that StumbleUpon plugin and all its tags and their mess making!