User Agent: Mozilla/5.0 (Windows NT 6.3; WOW64; rv:41.0) Gecko/20100101 Firefox/41.0 Build ID: 20150929144111 Steps to reproduce: Playing a Flash-based game, several other tabs open. Actual results: Prior to FF 41.0.1, FF would freeze during the occasional Flash-based game, owing to high memory usage. The current release would freeze often during Flash-based games, with no pattern recognizable or certain action made. Expected results: According to FF 41.0.1 release notes, hanging issues ought to be solved by now with Flash plugins running.

(In reply to Rainer Brinkmann from comment #0) > Steps to reproduce: > > Playing a Flash-based game, several other tabs open. Please post actual steps to reproduce the issue, including the link to the page in question. Can you reproduce the problem in a brand new profile with just one tab open? https://support.mozilla.org/kb/profile-manager-create-and-remove-firefox-profiles

I see a lot of complaints about this in Army of Awesome written in Japanese. So, I believe that we have something new regression in 41. One tweet claimed that when he/she downgrade his/her Firefox to 40, the hang-up isn't reproduced. And somebody said that this is reproduced in any websites which use Flash Player. And also this feedback (https://input.mozilla.org/ja/dashboard/response/5632397) claims that this is reproduced with new profile. Unfortunately, I cannot reproduce this bug, though.

I can reproduce this problem　on my PC. Firefox : Mozilla/5.0 (Windows NT 6.3; WOW64; rv:41.0) Gecko/20100101 Firefox/41.0 PC: TOSHIBA dynabook D712/V7HW OS: Windows 8.1 64bit (Japanese Edition) Display Adapter : Intel(R) HD Graphics 4000 Version : 10.18.10.3345 Flash Player: NPSWF32_19_0_0_185.dll

Can you please try this test build? http://ftp.mozilla.org/pub/mozilla.org/firefox/try-builds/aklotz@mozilla.com-ee278c419e02/try-win32/firefox-41.0.en-US.win32.installer.exe

(In reply to Aaron Klotz [:aklotz] (please use needinfo) from comment #4) > Can you please try this test build? > http://ftp.mozilla.org/pub/mozilla.org/firefox/try-builds/aklotz@mozilla.com- > ee278c419e02/try-win32/firefox-41.0.en-US.win32.installer.exe Failed to start by error "Could not find the Mozilla runtime".

(In reply to Aaron Klotz [:aklotz] (please use needinfo) from comment #4) > Can you please try this test build? > http://ftp.mozilla.org/pub/mozilla.org/firefox/try-builds/aklotz@mozilla.com- > ee278c419e02/try-win32/firefox-41.0.en-US.win32.installer.exe Reports that improved problem by using above Nightly has been posted to MozillaZine.jp forum. http://forums.mozillazine.jp/viewtopic.php?t=15704&p=56169

(In reply to Masahiro YAMADA from comment #5) > (In reply to Aaron Klotz [:aklotz] (please use needinfo) from comment #4) > > Can you please try this test build? > > http://ftp.mozilla.org/pub/mozilla.org/firefox/try-builds/aklotz@mozilla.com- > > ee278c419e02/try-win32/firefox-41.0.en-US.win32.installer.exe > > Failed to start by error "Could not find the Mozilla runtime". xul.dll seems to be missing.

(In reply to Masahiro YAMADA from comment #7) > (In reply to Masahiro YAMADA from comment #5) > > (In reply to Aaron Klotz [:aklotz] (please use needinfo) from comment #4) > > > Can you please try this test build? > > > http://ftp.mozilla.org/pub/mozilla.org/firefox/try-builds/aklotz@mozilla.com- > > > ee278c419e02/try-win32/firefox-41.0.en-US.win32.installer.exe > > > > Failed to start by error "Could not find the Mozilla runtime". > > xul.dll seems to be missing. I am able to run successfully by installing the firefox-41.0.en-US.win32.installer.exe. xul.dll also contains. Please try clean install or custom install to another folder.

(In reply to EarlgreyTea from comment #8) > (In reply to Masahiro YAMADA from comment #7) > > (In reply to Masahiro YAMADA from comment #5) > > > (In reply to Aaron Klotz [:aklotz] (please use needinfo) from comment #4) > > > > Can you please try this test build? > > > > http://ftp.mozilla.org/pub/mozilla.org/firefox/try-builds/aklotz@mozilla.com- > > > > ee278c419e02/try-win32/firefox-41.0.en-US.win32.installer.exe > > > > > > Failed to start by error "Could not find the Mozilla runtime". > > > > xul.dll seems to be missing. > > I am able to run successfully by installing the > firefox-41.0.en-US.win32.installer.exe. > xul.dll also contains. > Please try clean install or custom install to another folder. It was caused by AntiVirus software. xul.dll is removed by Norton Internet Security. After restoring xul.dll, it seems to work fine.

According to comment 6 and comment 9, your try build works well. I hope that it'll be fixed in 42 Beta. Could you take this bug?

[Tracking Requested - why for this release]: I see a lot of users who complain about this bug in Army of Awesome even only with Japanese tweets. So, not fixing this bug may make more damage to our marketing share. Fortunately, looks like that Aaron Klotz [:aklotz] has a patch for this bug. https://treeherder.mozilla.org/#/jobs?repo=try&revision=ee278c419e02

(In reply to Masahiro YAMADA from comment #9) > (In reply to EarlgreyTea from comment #8) > > (In reply to Masahiro YAMADA from comment #7) > > > (In reply to Masahiro YAMADA from comment #5) > > > > (In reply to Aaron Klotz [:aklotz] (please use needinfo) from comment #4) > > > > > Can you please try this test build? > > > > > http://ftp.mozilla.org/pub/mozilla.org/firefox/try-builds/aklotz@mozilla.com- > > > > > ee278c419e02/try-win32/firefox-41.0.en-US.win32.installer.exe > > > > > > > > Failed to start by error "Could not find the Mozilla runtime". > > > > > > xul.dll seems to be missing. > > > > I am able to run successfully by installing the > > firefox-41.0.en-US.win32.installer.exe. > > xul.dll also contains. > > Please try clean install or custom install to another folder. > > It was caused by AntiVirus software. xul.dll is removed by Norton Internet > Security. > After restoring xul.dll, it seems to work fine. xul.dll was detected as "Suspicious.Cloud.7.EP"

Not tracking as we are already tracking the dup.