733651 - Snippet fails to load on about:home due to XMLHttpRequest.open error

Status: RESOLVED FIXED

(Firefox :: General, defect)

Description

[Frank Yan (:fryn)]

Steps to reproduce:

1. Open Firefox so that about:home is the page immediately loaded and the update branch is taken in the function loadSnippets(). (This can artificially be induced by setting window.localStorage["snippets-last-update"] to 0 and then restarting Firefox without session restore enabled.)
2. No snippet appears, because the following exception is thrown:

Error: uncaught exception: [Exception... "Component returned failure code: 0x805e0006 [nsIXMLHttpRequest.open]"  nsresult: "0x805e0006 (<unknown>)"  location: "JS frame :: chrome://browser/content/abouthome/aboutHome.js :: loadSnippets :: line 223"  data: no]

I'm not exactly sure why this happens, but since it corrects itself upon a reload, my guess is that the XMLHttpRequest cannot be properly initialized.

This happens already on about:home in Firefox stable and is not due to the new visual refresh code.

Comment 1

[Frank Yan (:fryn)]

Attachment: workaround to ensure that at least the default snippets load

Here's a workaround to ensure that at least the default snippets load.

We should still investigate why XMLHttpRequest.open throws.

Comment 2

[Marco Bonardo [:mak]]

Comment on attachment 603582 [details] [diff] [review]
workaround to ensure that at least the default snippets load

please file a follow-up to investigate reasons for the exception and add a comment there pointing to that bug.

Comment 3

[Frank Yan (:fryn)]

Pushed to fx-team:
https://hg.mozilla.org/integration/fx-team/rev/63612df32193

Filing followup next.

Comment 4

[Marco Bonardo [:mak]]

https://hg.mozilla.org/mozilla-central/rev/63612df32193

backported with bug 711157

Comment 5

[Ioana (away)]

Mozilla/5.0 (Windows NT 6.1; rv:13.0) Gecko/20100101 Firefox/13.0
BuildID: 20120528154913

I evaluated window.localStorage["snippets-last-update"]=0; in the Error Console and restarted Firefox. I didn't get the error from comment 0, but I got:

Error: self._interfaceBuilder is undefined
Source File: resource://testpilot/modules/setup.js
Line: 260 

Frank, is that ok or should I set window.localStorage["snippets-last-update"] to 0 some other way?

Comment 6

[Ioana (away)]

Regarding my previous message, when evaluating window.localStorage["snippets-last-update"]=0; in the Error Console, I get the following error:

Error: uncaught exception: [Exception... "Component returned failure code: 0x80040111 (NS_ERROR_NOT_AVAILABLE) [nsIDOMWindow.localStorage]"  nsresult: "0x80040111 (NS_ERROR_NOT_AVAILABLE)"  location: "JS frame :: javascript:%20window.localStorage["snippets-last-update"]=0; :: <TOP_LEVEL> :: line 1"  data: no]

Comment 7

[Frank Yan (:fryn)]

(In reply to Ioana Budnar [QA] from comment #6)

This bug doesn't need further verification.
Thanks.