Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.3a5pre) Gecko/20100427 Minefield/3.7a5pre When you install an add-on and you have already clicked the install button inside the software installation dialog, there is no way to cancel the installation. With the next restart of Firefox the add-on will be installed. Steps: 1. Open https://addons.mozilla.org/en-US/firefox/addon/6622 2. Click 'Add to Firefox' and accept the software installation 3. Open the Extensions pane of the Add-ons Manager I expect to see a button which let me cancel the installation of the already downloaded extension. But right now I have to restart Firefox and the extension will be installed, even when I do not want it.

If the extension is larger or the connection is slow, you can switch to the Addons Manager while the download is running. There is no way to cancel the download via the UI.

(In reply to comment #2) > There is no way to cancel the download via the UI. There is - one of the buttons of the download progress cancels (the other pauses). However, its not obvious yet due to bug 553482. However, I don't think there's a way to cancel once the install is finished but waiting for a restart. I don't even know if the API supports that - Dave?

Calling cancel() on the AddonInstall should cancel the install.

(In reply to comment #0) > I expect to see a button which let me cancel the installation of the already > downloaded extension. But right now I have to restart Firefox and the extension > will be installed, even when I do not want it. Once the add-on is download and is in the add-on manager, it should have a "Remove" button like the other add-ons that uninstalls it.

Removing keyword uiwanted - please add back if more is needed here.

(In reply to comment #6) > Created an attachment (id=448118) [details] > Mockup: Removing an add-on immediately after installation > > (In reply to comment #0) > > I expect to see a button which let me cancel the installation of the already > > downloaded extension. But right now I have to restart Firefox and the extension > > will be installed, even when I do not want it. > > Once the add-on is download and is in the add-on manager, it should have a > "Remove" button like the other add-ons that uninstalls it. But you have to restart to see it. Right now, if an addon is installed, it only says "ready to install" restart now. You can't remove it until after you restart.

Needed by string freeze

Does what the mockup illustrates: Adds a button to cancel an installation (which only applies to non-restartless installs, obviously). Once you hit the cancel button, you get the option to undo (ie, continue the installation). The undo notification is transient, like the existing undo uninstall notice.

Note: Uncovered bug 587587 while working on this.

*sigh* I realised I ended up partially implementing this in bug 585950. My version matches the latest mockups that Boriss gave me however your version looks to have undoing the cancelling which mine doesn't. I think the best plan is for me to get bug 585950 up for review today and then we'll see about applying the stuff here on top of it.

Think everything here will be fixed by the mega-patch in bug 585950.

Since bug 585950 implemented cancelling installs I think its best to morph this bug to be about being able to undo that, same as we can undo uninstalling things. The patch here looks to do that, however I don't think having that feature blocks the release, which kind of sucks considering the work Blair put in :(

(In reply to comment #15) > which kind of sucks considering the work Blair put in :( Meh. Important thing is fixed -> I'm happy.