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Why I Have Sluggish Flash/HTML5 Animation in Firefox?

  • 2 replies
  • 1 has this problem
  • 18 views
  • Last reply by cor-el

Boris_yo
Boris_yo
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There are websites that have video playing back in the background and removethebackground.com is one of those sites. This kind of effect slows browser's response almost to a crawl unless I switch to another tab.

I have restarted Firefox in safe-mode with all addons disabled and video was playing smooth. This indicated to me that there was problem with addons and extensions and I disabled them all manually one-by-one after restarting in normal mode. But video was sluggish again despite all addons and extensions I disabled.

This is not clear to me. Are there other things that Firefox not shows me which can be disabled?

There are websites that have video playing back in the background and removethebackground.com is one of those sites. This kind of effect slows browser's response almost to a crawl unless I switch to another tab. I have restarted Firefox in safe-mode with all addons disabled and video was playing smooth. This indicated to me that there was problem with addons and extensions and I disabled them all manually one-by-one after restarting in normal mode. But video was sluggish again despite all addons and extensions I disabled. This is not clear to me. Are there other things that Firefox not shows me which can be disabled?

All Replies (2)

Nostromov
Nostromov
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Just btw., werx fine with:

Z68A-G43 (G3) - i7-3770 - Vengeance 2x4GB 2133MHz - GTX 650 Gainward - WD 1TB 64MB SATA - Win7 Pro/64 SP1 / Trusty Xfce AMD64

cor-el
cor-el
  • Moderator
  • Top 10 Contributor
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You can try to disable hardware acceleration in Firefox.

  • Tools > Options > Advanced > General > Browsing: "Use hardware acceleration when available"

You need close and restart Firefox after toggling this setting.

In Firefox Safe mode these changes are effective:

  • all extensions are disabled (about:addons)
  • default theme is used (no persona)
  • userChrome.css and userContent.css are ignored (chrome folder)
  • default toolbar layout is used (localstore-safe.rdf file)
  • JavaScript JIT compilers are disabled (about:config page: javascript.options.*jit)
  • hardware acceleration is disabled (Options > Advanced > General)
  • plugins are not affected
  • preferences are not affected