Mozilla/5.0 (Windows NT 6.1; WOW64; rv:39.0) Gecko/20100101 Firefox/39.0 Nightly 39.0a1, build ID: 20150303030230. STR: 1. Open Firefox; 2. Open 6 different websites and wait for them to be completely loaded; 3. Enter group tabs (ctrl+shift+e); 4. Resize the tab group. Expected Results: The tab group is resized without any visual glitch. Actual Results: The tabs thumbnails flicker (black/normal) after resizing the group and releasing the mouse click. Notes: This issue only reproduces on Nightly.

Cornel, Is this Win64 only? Clean profile? e10s only? Also, if you have time, can you find a regression window? If not, needInfo me back and I'll dig into it.

I can reproduce with e10s, but not without e10s. Reproduced on Windows7 and Ubuntu14.04. did not test on Mac. Regression window: https://hg.mozilla.org/mozilla-central/pushloghtml?fromchange=cc2d8bdbccb8&tochange=f2d7d694aae5 Triggered by: Bug 698371

Confirming, I can reproduce this on Win7 w/32-bit Nightly. Blocking e10s rollout on this but definitely a polish bug so m8.

This also affects Ubuntu 12.04 32-bit and Mac OS X 10.9.5 using clean profiles on Nightly with e10s enabled. Thanks Alice for the regression window!

try push: https://treeherder.mozilla.org/#/jobs?repo=try&revision=29d6fa51f59c

(In reply to Jim Mathies [:jimm] from comment #7) > try push: > https://treeherder.mozilla.org/#/jobs?repo=try&revision=29d6fa51f59c test failure: 397 INFO TEST-UNEXPECTED-FAIL | browser/components/tabview/test/browser_tabview_bug599626.js | uncaught exception - InvalidStateError: An attempt was made to use an object that is not, or is no longer, usable at chrome://browser/content/tabview.js:6183

The test failure was due to the canvas created by PageThumbs going out of scope due to shutdown. The line that triggered is was the drawImage call. I added a try catch around the async response TabCanvas_update code and that cleaned it up.

Comment on attachment 8649516 [details] [diff] [review] patch v.2 >+ gPageThumbnails.captureToCanvas(this.tab.linkedBrowser, temp, () => { >+ try { >+ let ctx = this.canvas.getContext('2d'); >+ this.canvas.width = aWidth; >+ this.canvas.height = aHeight; >+ ctx.drawImage(temp, 0, 0); >+ this._sendToSubscribers("painted"); >+ } catch (ex) {} >+ }); Please restrict the try/catch to the problematic call (drawImage) and only catch the expected exception, e.g.: > gPageThumbnails.captureToCanvas(this.tab.linkedBrowser, temp, () => { > let ctx = this.canvas.getContext("2d"); > this.canvas.width = aWidth; > this.canvas.height = aHeight; > try { > ctx.drawImage(temp, 0, 0); > } catch (ex if ex.name == "InvalidStateError") { > // Can't draw anymore if we're shutting down > return; > } > this._sendToSubscribers("painted"); > }; r+ if this works as I imagined, otherwise please re-request review

Reproduce this bug on Firefox nightly 39.0a1 (2015-03-04) on windows 7 64 bit The bug's fix is verified on latest Nightly 43.0a1 (Build ID:20150825030212) Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:43.0) Gecko/20100101 Firefox/43.0

Confirming the fix on latest Nightly, build ID: 20150825030212. Tested using Mac OS X 10.9.5, Ubuntu 12.04 32-bit, Windows 7 64-bit and Windows 10 64-bit.