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Reviews for Undo Close Tab

Undo Close Tab by Manuel Reimer

4.7 Stars out of 5
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Review by TwoCables
by TwoCables, 5 years ago
I've been away from Firefox for about 4 months. I came back to it a couple of days ago, updated to 78.0.2, and discovered that my closed tabs history gets deleted between Firefox sessions. This isn't the way it was working before. The only thing I changed is, I updated Firefox.

So I disabled this extension and discovered that it was the culprit. I switched to Undo Close Tab Button by Button Guy, and not only does my closed tab history remain between sessions like it used to, but the button can be a menu instead of just a simple one-click button. I prefer the menu. For some reason, I couldn't right-click the Undo Close Tab button anymore either. I don't know what happened to this extension, but it used to be the best and now it's the worst.

Edit: I doubt I'm the first one to notice. It's much more likely that I'm just the first one to say something about it.

Developer response

posted 5 years ago
Actually you are the first one actually noticing this. The closed tab history is only kept for up to the *last* session but if you tend to close Firefox pretty often this, of course, may be a problem.

The reason for this is that I can't just rely on the Firefox built in sessions API and its closed tab history. If I do so, then, after some restarts, you will run into a bug that causes random tabs or even windows to restore as the internal IDs get reused which causes duplicated IDs. See here: https://bugzilla.mozilla.org/show_bug.cgi?id=1538119

To work around this problem, I move the Firefox internal closed tab history into a list in my Add-on to clear it. From this point I use a combination of my internal list (for tabs from the last session) and the Firefox built-in list (for tabs closed since browser start). This way I can be sure that no duplicated IDs will exist at any time and always the expected tabs or windows get restored. The only downside is that my internal list does not survive a browser restart. I could save it into storage but this could be a potential privacy problem for people who don't use session restore (and before you ask: Mozilla does not tell Add-ons about the session restore enabled status).

So currently with the existing bugs there are only two options:
a) Accept the small downside of only having last closed tabs for up to the last browser session
b) Randomly restore stuff you don't expect.

As most people don't even remember that they had interesting tabs open for more than one session into the past and random restores can be really annoying, I decided to go with a)
563 reviews