This bug also affects me. I use Arch Linux and the bug started manifesting itself after I installed a new NVIDIA GPU (GeForce GTX 650, driver version 304.51). I used integrated Intel GPU (Intel HD Graphics 2000 in a Sandy Bridge CPU) before and the problem was not present.
"opacity: .99" can be set permanently for the body element of all visited web pages by editing $HOME/.mozilla/firefox/[profile-directory]/chrome/userContent.css so that it contains: body { opacity: .99 ! important; } This is a usable workaround, it doesn't seem to affect rendering of web pages aside from removing the bolding issue. -- You received this bug notification because you are a member of Desktop Packages, which is subscribed to firefox in Ubuntu. https://bugs.launchpad.net/bugs/1015751 Title: Text is randomly rendered bold when scrolling Status in “firefox” package in Ubuntu: Confirmed Bug description: I noticed that on some sites (reddit.com and a few forums) text appears randomly bolded, even if it shouldn't be. Its appearance reverts to a normal state after selecting the text, taking a screenshot, opening a window over the text etc. What you expected to happen: Firefox displaying normal text. What happened instead: Firefox displays randomly bolded text when scrolling a website. ProblemType: Bug DistroRelease: Ubuntu 12.04 Package: firefox 13.0+build1-0ubuntu0.12.04.1 ProcVersionSignature: Ubuntu 3.2.0-25.40-generic-pae 3.2.18 Uname: Linux 3.2.0-25-generic-pae i686 NonfreeKernelModules: nvidia AddonCompatCheckDisabled: False AlsaVersion: Advanced Linux Sound Architecture Driver Version 1.0.24. ApportVersion: 2.0.1-0ubuntu8 Architecture: i386 AudioDevicesInUse: USER PID ACCESS COMMAND /dev/snd/controlC0: romano 1832 F.... pulseaudio /dev/snd/pcmC0D0p: romano 1832 F...m pulseaudio BuildID: 20120601173917 CRDA: Error: command ['iw', 'reg', 'get'] failed with exit code 1: nl80211 not found. Card0.Amixer.info: Card hw:0 'NVidia'/'HDA NVidia at 0xdbff8000 irq 22' Mixer name : 'Realtek ALC662 rev1' Components : 'HDA:10ec0662,18493662,00100101' Controls : 32 Simple ctrls : 17 Channel: release Date: Wed Jun 20 20:36:18 2012 DefaultProfilePrefErrors: Unexpected character before close parenthesis @ [Profile]/extensions/{e4a8a97b-f2ed-450b-b12d-ee082ba24781}/defaults/preferences/greasemonkey.js:4 ForcedLayersAccel: False IfupdownConfig: auto lo iface lo inet loopback InstallationMedia: Ubuntu 12.04 LTS "Precise Pangolin" - Release i386 (20120423) IpRoute: default via 192.168.1.1 dev eth0 proto static 169.254.0.0/16 dev eth0 scope link metric 1000 192.168.1.0/24 dev eth0 proto kernel scope link src 192.168.1.2 metric 1 IwConfig: lo no wireless extensions. eth0 no wireless extensions. MostRecentCrashID: bp-5da2c515-dd81-4bf0-8a39-9929f2120503 PciNetwork: ProcEnviron: PATH=(custom, no user) LANG=pl_PL.UTF-8 SHELL=/bin/bash Profiles: Profile0 (Default) - LastVersion=13.0/20120601173917 (In use) Profile1 - LastVersion=13.0/20120601173917 Profile2 - LastVersion=13.0/20120601173917 RelatedPackageVersions: gnome-shell 3.4.1-0ubuntu2 icedtea-6-plugin 1.2-2ubuntu1 rhythmbox-mozilla 2.96-0ubuntu4 totem-mozilla 3.0.1-0ubuntu21 RfKill: 0: hci0: Bluetooth Soft blocked: no Hard blocked: no RunningIncompatibleAddons: False SourcePackage: firefox SubmittedCrashIDs: bp-5da2c515-dd81-4bf0-8a39-9929f2120503 UpgradeStatus: No upgrade log present (probably fresh install) dmi.bios.date: 04/09/2008 dmi.bios.vendor: American Megatrends Inc. dmi.bios.version: P1.50 dmi.board.name: ALiveNF6P-VSTA dmi.chassis.asset.tag: To Be Filled By O.E.M. dmi.chassis.type: 3 dmi.chassis.vendor: To Be Filled By O.E.M. dmi.chassis.version: To Be Filled By O.E.M. dmi.modalias: dmi:bvnAmericanMegatrendsInc.:bvrP1.50:bd04/09/2008:svnToBeFilledByO.E.M.:pnToBeFilledByO.E.M.:pvrToBeFilledByO.E.M.:rvn:rnALiveNF6P-VSTA:rvr:cvnToBeFilledByO.E.M.:ct3:cvrToBeFilledByO.E.M.: dmi.product.name: To Be Filled By O.E.M. dmi.product.version: To Be Filled By O.E.M. dmi.sys.vendor: To Be Filled By O.E.M. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/firefox/+bug/1015751/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : desktop-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp