815237 - Windows tab previews for unrestored tabs are shown as if they were in loading

Status: NEW

(Firefox :: Shell Integration, defect)

Description

[Marco Castelluccio [:marco]]

In the error console there's this error:
[Exception... "An attempt was made to use an object that is not, or is no longer, usable"  code: "11" nsresult: "0x8053000b (InvalidStateError)"  location: "resource://gre/modules/WindowsPreviewPerTab.jsm Line: 322"]

That line is ctx.drawImage(this.canvasPreview, 0, 0); in drawThumbnail.

Comment 1

[alex_mayorga]

On Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:20.0) Gecko/20121216 Firefox/20.0 ID:20121216030851 I get slight variants that appear at random:

Error: [Exception... "An attempt was made to use an object that is not, or is no longer, usable"  code: "11" nsresult: "0x8053000b (InvalidStateError)"  location: "resource://gre/modules/WindowsPreviewPerTab.jsm Line: 323"]
Source File: resource://gre/modules/WindowsPreviewPerTab.jsm
Line: 323

Error: [Exception... "An attempt was made to use an object that is not, or is no longer, usable"  code: "11" nsresult: "0x8053000b (InvalidStateError)"  location: "resource://gre/modules/WindowsPreviewPerTab.jsm Line: 315"]
Source File: resource://gre/modules/WindowsPreviewPerTab.jsm
Line: 315

Steps:

1 Enable "Show tab previews in the Windows taskbar"[1]
2 Hover the mouse over Nightly's taskbar icon
3 Hover the mouse over one of the tab previews

1 https://support.mozilla.org/en-US/kb/tab-preferences-and-settings

Comment 2

[alex_mayorga]

Duplicate of bug 545077 perhaps?

Comment 3

[Rob Arnold [:robarnold]]

I'm afraid I don't have time to work on this feature (haven't for years really). That said, this probably isn't a difficult bug for someone to fix if they're willing.

Comment 4

[alex_mayorga]

(In reply to Marco Castelluccio [:marco] from comment #0)
> 
> That line is ctx.drawImage(this.canvasPreview, 0, 0); in drawThumbnail.

I think this is at http://mxr.mozilla.org/mozilla-central/source/browser/modules/WindowsPreviewPerTab.jsm#315 right?

Comment 5

[Marco Castelluccio [:marco]]

(In reply to alex_mayorga from comment #4)
> I think this is at
> http://mxr.mozilla.org/mozilla-central/source/browser/modules/
> WindowsPreviewPerTab.jsm#315 right?

No, at http://mxr.mozilla.org/mozilla-central/source/browser/modules/WindowsPreviewPerTab.jsm#323