Mozilla/5.0 (Windows; U; Windows NT 5.0; en-US; rv:1.9a1) Gecko/20060620 Minefield/3.0a1 ID:2006062002 [cairo] repro: 1.open FF 2.open an extra tab 3.close that tab Error: tabbrowser.mTabs[i] has no properties Source file: file:///C:/Programmas/Firefox/ff30C/firefox/components/nsSessionStore.js Line: 816 followed by Error: Component returned failure code: 0x80004005 (NS_ERROR_FAILURE) [nsIDOMXULElement.boxObject] Source file: chrome://global/content/bindings/browser.xml

This sounds to me like the regression of bug 338441 which should get fixed with bug 318168.

Facing in under ubuntu 6.06 LTS. OS -> All ?

(In reply to comment #1) > This sounds to me like the regression of bug 338441 which should get fixed with > bug 318168. > it first showed up last night after bug 254021 was checked in though

This fixes the issue for me. I don't see how bug 254021 could have caused this without SessionStore being enabled, so it's probably rather due to bug 337320 (as mentioned in bug 342155).

(In reply to comment #4) > Created an attachment (id=226366) [edit] > fix (see bug 318168) > > This fixes the issue for me. I don't see how bug 254021 could have caused this > without SessionStore being enabled, so it's probably rather due to bug 337320 > (as mentioned in bug 342155). > SessionStore has been enabled on trunk for several days, and worked fine until 254021 was checked in.

Indeed. The problem is thus probably rather that SessionStore tries to capture the tab one last time while it's already being destroyed (however I don't see how that issue could be fixed before the new tab related events are added in bug 322898 or bug 318168).

I think this is related to something I've seen with bug #318168, in that we need to clear the _browsers cache. see bug #318168 comment #36.

(In reply to comment #7) I thought so, too, originally, but it in fact rather seems to be related to SessionStore trying to access a tab which has already been removed from mTabContainer. Apart of the _browsers fix, SessionStore must be able to observe the TabClose event and react to it (instead of DOMNodeRemoved) - see my comment #6.

based on simon's comments, re-assigning to dietrich.

Added dependency on bug 334839, which is for adding support for the new tab events to sessionstore, once they're available.

Fixed by bug 318168 and bug 334839.