This would be a 5 if "Compare by page title instead of or in addition to the URL" worked, but it doesn't.
It only compares all titles and ignores the URLs. So all copilot tabs deleted even though they are different topics and urls.
That is "Compare ONLY title".
It should compare URL AND title, to exclude the same URL with different titles (re-named tabs), so the renamed tabs can be manually selected in a second run after bulk delete, to keep them.

I nearly lost hundreds of renamed tabs because of misleading wording and bad code. And can't use bulk delete at all.

Also, feature requests :)

1. ignore query- can this exclude anything after the URL appended by & or ? (youtube list and timestamps, trackers etc) - it seems to exclude only Google search parameters which of course we do not want to ignore?

2. Is it possible to have the full titles accessible in the list, either a horizontal scrollbar, or tooltips of title and URL like FF bookmarks toolbar, or selectable overflow text (like in windows explorer file properties path box)? Often retitled tabs are only different at the end.

Absolutely perfect! Customizable, good-looking and works perfectly. Thank you, I really enjoy using it :-)

4.1.5に更新した所、保存したセッションを開いて、さらに同一タブを開いたときに重複を検知できなくなった。
4.2.1 で治ってることを確認した。修正お疲れ様です

Works really well. You can configure it to ignore certain parts of the URL like after the search (?) part or hash (#) part of the URL as some sites will generate duplicate tabs with these parts different.

Works so sell that,
when I swithed to another pc, and the dup tabs won't close after pressing the shortcut key,
it took me quite long to realize that i havent installed this extension on new pc yet.

Works great. I really like the "Filters" options - without them the extension would be pretty much useless to me.

Absolutely beautiful. Exactly what I wanted. Automatically closing older duplicate tabs when a new duplicate is opened should be a stock option in firefox.

Excellent.

Drawback: the add-on seems to have been abandoned 4 years ago, as seen on Github:
https://github.com/Peuj/duplicate-tabs-closer

But I find a bug:
Whatever your choice in "Priority" parameter in the Options, the add-on always keeps the oldest visited tab. This parameter seems to not work at all.

And I also have two little requests:
- First one: it would be nice not to include the tabs "New tab" in the list.
- And second one: it would be nice to disregard (ignore) a final "/".

Both requests could have their checkbox in the Option page (with On by default).

But I don't know what to think, given that the developments seem to have been abandoned 4 years ago.

Write about my experience with this add-on? I wasted hours trying to figure out why I could have only one tab per domain. It didn't matter if the url was completely different. Utter POS because the PEUJ who designed it doesn't even know the meaning of "duplicate". IT MEANS "EXACTLY THE SAME", got that? Read again.

big productivity QoL for disorganized compulsive browsers (user)