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FireFox stealing app focus

  • 4 replies
  • 2 have this problem
  • 1 view
  • Last reply by dgerton

dgerton
dgerton
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Setup: FireFox 26.0 is running on OSX and open to a web page that uses javascript. The FireFox window can either be in the background or minimized, while any other application is in the foreground.

Problem: If the web page in FireFox inserts an HTML5 <embed> tag via javascript, FireFox mistakenly takes the application focus at that OS level.

To be clear, this behavior is inconsistent with the other browsers. It does not happen with Chrome, Safari nor Opera on OSX, nor should it. A well-behaved should remain in the background if put there by the user.

I suspect, given the number of support requests about this issue, that it has not been forwards to your developers.

Setup: FireFox 26.0 is running on OSX and open to a web page that uses javascript. The FireFox window can either be in the background or minimized, while any other application is in the foreground. Problem: If the web page in FireFox inserts an HTML5 <embed> tag via javascript, FireFox mistakenly takes the application focus at that OS level. To be clear, this behavior is inconsistent with the other browsers. It does not happen with Chrome, Safari nor Opera on OSX, nor should it. A well-behaved should remain in the background if put there by the user. I suspect, given the number of support requests about this issue, that it has not been forwards to your developers.

All Replies (4)

guigs
guigs
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Hi, welcome to the support forum, and thank you for letting us know about this I would love to know the steps you are taking to notice this behavior, with this we can create a bug and make a clear message to the developer.

What does it look like when it focuses to the OS?

Thank you!

dgerton
dgerton Question owner
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In FireFox visit this JSFiddle I created to demonstrate this problem. Switch to another application, an email program for instance

After 10 seconds a sound will play and FireFox will have moved on top of and taken away keyboard input from the email application.

It occurs to me that this is also a security risk. A malicious web page could be designed to cause a DOS attack of sorts, preventing the user from switching away from FireFox.

guigs
guigs
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Ok, I have the same issue on Mac 10.8 with firefox 27, 28, but not nightly. Please let me know if this also is reproducible for you in Firefox Nightly version.

I have filed this bug in the meantime and someone will be taking a look at it soon. Thank you for reporting this.

Bug 961210 - firefox can be used to hijack focused application with Dom object https://bugzilla.mozilla.org/show_bug.cgi?id=961210

dgerton
dgerton Question owner
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I can reproduce the problem in Nightly also. Initially, Quicktime is blocked and no sound play.

If you activate Quicktime, the sounds start playing and the focus is again captured.