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Firefox 33.0 lags in text typing/ selecting/ deleting & switching tabs

  • 2 replies
  • 2 have this problem
  • Last reply by cor-el

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After an automatic update from FF 32.0.3 to FF 33.0 on 17 Oct 2014, there had been a severe browser lag. Each user action or input results in a lag lasting 1–5 secs each, making the browser very difficult & unpleasant to use.

  • Typing Text: 1–2 secs before each letter appears
  • Highlighting Text (self-typed & web-rendered text): 2–3 secs before desired text is highlighted, & only partially (eg. For "impossible", can only highlight "imposs" or "ssible")
  • Deleting Text: 1–2 secs before each letter gets deleted
  • Switching Between Tabs: 2–5 secs for switch
  • Webpage Scrolling: 1–2 secs for each turn (for mouse wheel) or down-swipe (for touchpad)

All of the above issues occur everytime despite system restart, having only 1–2 tabs open, & even when FF is the only application running. I have not encountered the aforementioned problems in FF 32.0.3 & earlier FF versions, or in other browsers.

Other than FF being automatically updated to FF 33.0 on 17 Oct 2014, there was no other change (ie. no application install/ uninstall, no Windows update) that day or the preceding few days.

The lag disappears if FF 33.0 is run in safe mode with all add-ons disabled. But testing with add-ons disabled one by one does not isolate which add-on (if any) might be involved.

  • Laptop: Lenovo IdeaPad Y460
  • OS: Windows 7 SP 1
  • Display Adapters: ATI Mobility Radeon HD5650 (driver: 8.702.5.0 latest version), Intel HD Graphics (driver: 8.702.5.0 latest version)
  • Firefox User Experience: FF 33.0 (very bad lag), FF 32.0.3 & earlier (all function ok)
  • Browser Add-ons & Plugins: All latest versions

What I eventually did (a few days before reporting here after registering a user account): Since I was unable to resolve the problem, I performed a successful system restore, but the rolled-back browser (FF 32.0.3) was unable to launch (error code: "can't load XPCOM"). Subsequently, I resorted to installing a fresh copy of FF 32.0.3.

Since 17/18 Oct 2014, I have encountered a couple of reports about similar lag issues in FF 33.0 (& possibly since FF 32.0.* for some users). The collective symptoms & feedback suggest that it is probably not add-ons causing the issue, but some newly-created incompatibility or conflict with certain (or combinations of) display/ graphics adapter(s). So far, the reported affected adapters that I have come across include the ATI Mobility Radeon HD5000 series, Intel HD Graphics, & NVIDIA GeForce.

The temporary workaround appears to be disabling the hardware acceleration option. But since this is not a long-term solution, I am holding off updating to FF 33.0 (again) or to the just-released FF 33.0.1, until this issue is officially recognized & resolved.

Note:- Some users with text/ tab lagging problems also reported slowness wrt video &/or flash pages, which I can't verify because I had not tested FF 33.0 on video/ flash pages before reinstalling FF 32.0.3. (The text, tab & scrolling lags are enough to keep me away from browsing anything but the most basic webpages.)

Some Feedback References (for affected users & FF developers):

Possibly related to the same bug:-

Modified by hairyfox

All Replies (2)

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Try disabling graphics hardware acceleration. Since this feature was added to Firefox, it has gradually improved, but there still are a few glitches.

Start Firefox in Safe Mode {web link} While you are in safe mode;

Type about:preferences<Enter> in the address bar

Select Advanced > General. Look for and turn off Use Hardware Acceleration.

Poke around safe web sites. Are there any problems?

Then restart.

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Create a new profile as a test to check if your current profile is causing the problem.

See "Creating a profile":

If the new profile works then you can transfer files from a previously used profile to the new profile, but be cautious not to copy corrupted files to avoid carrying over problems.