User Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:40.0) Gecko/20100101 Firefox/40.0 Build ID: 20150727174134 Steps to reproduce: goto "about:addons" in awesome bar Actual results: failed to load about:addons page and firefox hangs with high CPU load Expected results: add-on manager loads properly

also note: (1) this does not happen before ff40, and (2) this happens even if omtc is perf off (layers.offmainthreadcomposition.enabled = false).

(In reply to marvinhk from comment #1) > also note: (1) this does not happen before ff40, and (2) this happens even > if omtc is perf off (layers.offmainthreadcomposition.enabled = false). Please download and run https://github.com/mozilla/mozregression/releases/download/gui-0.3/mozregression-gui.exe then follow these steps: 1. Select these values on the first page then click next > Appliction: firefox > Bisection: nightlies > Bits: 64 > Search fix: unchecked 2. Enter these values on the second page then click next > Last known good date: 30/03/2015 > First known bad date: 11/05/2015 3. On the third page just leave everything blank and click Finish This should start downloading Nightly builds for you to test. After testing each build it will prompt you to indicate if the build was good or not (ie. if it didn't reproduce the bug it's good). At the end of the process you'll be given a pushlog URL. Please report back to this bug once you have that information.

(In reply to Anthony Hughes, QA Mentor (:ashughes) from comment #2) > At the end of the process you'll be given a pushlog URL. Please report back > to this bug once you have that information. results are all good

(In reply to Anthony Hughes, QA Mentor (:ashughes) from comment #2) > At the end of the process you'll be given a pushlog URL. Please report back > to this bug once you have that information. pushlog_url: https://hg.mozilla.org/mozilla-central/pushloghtml?fromchange=26d6392b5403&tochange=502e1a5e722f

(In reply to marvinhk from comment #3) > (In reply to Anthony Hughes, QA Mentor (:ashughes) from comment #2) > > At the end of the process you'll be given a pushlog URL. Please report back > > to this bug once you have that information. > > results are all good Then that means this bug is *not* in Firefox 40 and probably started happening later. Please check the following builds and report which one's are good or bad: http://archive.mozilla.org/pub/firefox/nightly/2015/07/2015-07-31-03-02-06-mozilla-central/firefox-42.0a1.en-US.win32.installer.exe http://archive.mozilla.org/pub/firefox/nightly/2015/07/2015-07-03-03-02-16-mozilla-central/firefox-42.0a1.en-US.win32.installer.exe http://archive.mozilla.org/pub/firefox/nightly/2015/06/2015-06-01-03-02-03-mozilla-central/firefox-41.0a1.en-US.win32.installer.exe http://archive.mozilla.org/pub/firefox/nightly/2015/05/2015-05-02-03-02-08-mozilla-central/firefox-40.0a1.en-US.win32.installer.exe http://archive.mozilla.org/pub/firefox/nightly/2015/04/2015-04-02-03-02-07-mozilla-central/firefox-40.0a1.en-US.win32.installer.exe http://archive.mozilla.org/pub/firefox/nightly/2015/03/2015-03-02-03-02-04-mozilla-central/firefox-39.0a1.en-US.win32.installer.exe

after further testing, problem probably not with firefox. about:addons can be accessed after disabling noscript v2.6.9.33 in safe mode. without disabling addons 39.0a1 crash in xpc::AddonWindowOrNull(JSObject*) https://crash-stats.mozilla.com/report/index/f129d5ed-0529-48c4-bf01-6a3562150801 https://crash-stats.mozilla.com/report/index/886c7cb0-995f-4d36-97b7-9264a2150801 other builds simply hangs.

Thanks, this would seem to imply a bug in NoScript. First, try seeing if updating to the latest version resolves this issue: https://addons.mozilla.org/en-US/firefox/addon/noscript/?src=ss If that doesn't work I suggest you work with the developer to troubleshoot this further: https://addons.mozilla.org/en-US/firefox/addon/noscript/?src=ss#developer-comments If it turns out this is a Firefox bug then we can reopen investigation on our end.