786577 - Javascript Type error: Can't access dead object when closing a tab in the background. Using dragupload with Firefox 15.0

Status: RESOLVED WONTFIX

(WebExtensions :: General, defect)

Description

[itsthewoo]

User Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:15.0) Gecko/20100101 Firefox/15.0
Build ID: 20120824154833

Steps to reproduce:

Closed background tab. It does not matter if you use the assigned mousebutton shortcut or the context menu. This only occurs when TabMix Plus v.0.4.0.3 is used.


Actual results:

Javascript error window pops up and returns after closing. Unable to put the error window in the background.


Expected results:

No error window.

Comment 1

[Cork]

That sounds like Tab Mix Plus is trying to access a window object after its tab has been closed (and the window object force destroyed). Firefox cuts all links to this object[1] when a tab is closed to fix a VERY common memory leak in extensions[2].

Try reporting/see if its already reported in there forum[3].

[1] http://blog.kylehuey.com/post/21892343371/fixing-the-memory-leak
[2] http://blog.mozilla.org/nnethercote/2012/07/19/firefox-15-plugs-the-add-on-leaks/
[3] http://tmp.garyr.net/forum/viewforum.php?f=2&start=15

Comment 2

[itsthewoo]

I don't know if I didn't recreate it properly before, but the error is now occurring even with TabMix Plus disabled.

Comment 3

[Jorge Villalobos [:jorgev] (he/him)]

Can you please paste the full error message? It could have some hints as to where the error is happening.

Comment 4

[itsthewoo]

It says exactly what the title says it says. "TypeError: can't access dead object."

Tried disabling Session Manager as well. Error is still coming up.

Comment 5

[itsthewoo]

It started doing it even when tabs weren't in the background. I rolled back to 14.01, and I am not having the issue anymore.

Comment 6

[Alex Pircher]

Similar error since upgrading from SeaMonkey 2.11 to 2.12, using Tab-Extensions Duplicate Tab and Tab Clicking Options (http://twanno.mozdev.org/).

It's not happening always when closing a tab, but when it is happening the error pops up every second and you are unable to use the browser, only a restart prevents further error-messages.

Comment 7

[Nicholas Nethercote [inactive]]

TabMix Plus will need to update for the changes.

Comment 8

[itsthewoo]

I disabled TabMix Plus and it still happened, albeit not immediately.

Comment 9

[Kris Maglione [:kmag]]

What other add-ons do you have installed? Can you post the contents of about:support?

Comment 10

[itsthewoo]

Attachment: about:support w/ addons

Comment 11

[itsthewoo]

I did a legitimate add-on isolation, and it looks like it's actually being caused by dragupload. I have disabled it in 15.01 with all other add-ons (including tab mix plus), and am no longer experiencing problems. I will update if otherwise.

Comment 12

[Nicholas Nethercote [inactive]]

Thanks for the update.  You might like to inform the author of dragupload.

I seem to remember something about TabMix Plus being easily broken by other add-ons -- Kris, do you know about this?

Comment 13

[itsthewoo]

Looks like dragupload is no longer supported (the URL is no longer available). The reviews on the add-ons download portal indicate the problem that I reported here.

Comment 14

[Dão Gottwald [:dao]]

It doesn't sound like this is fixed. Maybe wontfix?

Comment 15

[Alex Pircher]

I can confirm that after disabling dragupload-extension in SeaMonkey the error does not occur again so far.

Comment 16

[Jorge Villalobos [:jorgev] (he/him)]

Yes, the add-on hasn't been updated since June of last year. I'll mark it incompatible with Firefox 15 and above, to avoid confusion.

Comment 17

[Kris Maglione [:kmag]]

TabMix Plus is a common cause of incompatibilities, yes. It modifies a lot of tab APIs (mostly by string substitution and eval), so it's hard to play nice with it, but it's popular enough that most add-ons make special considerations.

Comment 18

[Danial Horton]

I think its negligent to say its a "common cause of incompatibilities" when you do not have data backing that statement up.