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firefox hangs when downloading large files

Posted

Firefox hangs when downloading large files. Take 100% CPU and I must kill it. Not possible to surf when it happens.

This happened

Every time Firefox opened

== downloading large files (1Gb or + )

Firefox hangs when downloading large files. Take 100% CPU and I must kill it. Not possible to surf when it happens. == This happened == Every time Firefox opened == downloading large files (1Gb or + )

Additional System Details

Installed Plug-ins

  • -3.0.40818.0
  • MozPlugger version 1.13.3, maintained by Louis Bavoil and Peter Leese, a fork of plugger written by Fredrik Hübinette.For documentation on how to configure mozplugger, check the man page. (type man mozplugger) Configuration file:/etc/mozpluggerrc Helper binary:mozplugger-helper Controller binary:mozplugger-controller Link launcher binary:mozplugger-linker Mozplugger: M4 parsing of config generated error
  • Version 1.0.6 Goldeneye, copyright 1996-2007 The VideoLAN Teamhttp://www.videolan.org/
  • This plug-in detects the presence of iTunes when opening iTunes Store URLs in a web page with Firefox.
  • Shockwave Flash 10.1 r53
  • The IcedTea NPR Web Browser Plugin (using IcedTea6 1.8 (6b18-1.8-4ubuntu3)) executes Java applets.

Application

  • User Agent: Mozilla/5.0 (X11; U; Linux i686; fr; rv:1.9.2.8) Gecko/20100723 Ubuntu/10.04 (lucid) Firefox/3.6.8

More Information

Paramètres de base de l'application
Nom
Firefox
Version
3.6.8
Répertoire de profil
Ouvrir le dossier correspondant
Plugins installés
about:plugins
Configuration de compilation
about:buildconfig
Extensions
Nom
Version
Activée
ID
Adblock Plus
1.2.1
true
FlashGot
1.2.1.28
true
{19503e42-ca3c-4c27-b1e2-9cdb2170ee34}
NewTabURL
2.2.0
true
newtaburl@sogame.cat
Novell Moonlight
2.3
true
moonlight@novell.com
Ubuntu Firefox Modifications
0.9rc2
true
ubufox@ubuntu.com
Xmarks
3.7.8
true
foxmarks@kei.com
Firebug
1.5.4
true
firebug@software.joehewitt.com
Préférences modifiées
Nom
Valeur
accessibility.typeaheadfind.flashBar
0
browser.history_expire_days
0
browser.history_expire_days.mirror
180
browser.places.importDefaults
false
browser.places.migratePostDataAnnotations
false
browser.places.smartBookmarksVersion
2
browser.places.updateRecentTagsUri
false
browser.startup.homepage
http://www.google.fr
browser.startup.homepage_override.mstone
rv:1.9.2.8
browser.tabs.autoHide
false
browser.tabs.forceHide
false
browser.tabs.warnOnClose
false
browser.tabs.warnOnOpen
false
dom.disable_window_move_resize
true
extensions.lastAppVersion
3.6.8
network.cookie.prefsMigrated
true
places.last_vacuum
1278010813
print.postscript.paper_size
A4
print.print_bgcolor
false
print.print_bgimages
false
print.print_colorspace
default
print.print_command
lpr $
print.print_downloadfonts
false
print.print_edge_bottom
0
print.print_edge_left
0
print.print_edge_right
0
print.print_edge_top
0
print.print_evenpages
true
print.print_footercenter
print.print_footerleft
&PT
print.print_footerright
&D
print.print_headercenter
print.print_headerleft
&T
print.print_headerright
&U
print.print_in_color
true
print.print_margin_bottom
0.500000012107193
print.print_margin_left
0.500000012107193
print.print_margin_right
0.500000012107193
print.print_margin_top
0.500000012107193
print.print_oddpages
true
print.print_orientation
0
print.print_pagedelay
500
print.print_paper_data
0
print.print_paper_height
279,40
print.print_paper_name
A4
print.print_paper_size_type
1
print.print_paper_size_unit
1
print.print_paper_width
215,90
print.print_plex_name
default
print.print_printer
couleur
print.print_resolution_name
default
print.print_reversed
false
print.print_scaling
1,00
print.print_shrink_to_fit
true
print.print_to_file
false
print.print_unwriteable_margin_bottom
56
print.print_unwriteable_margin_left
25
print.print_unwriteable_margin_right
25
print.print_unwriteable_margin_top
25
print.printer_Imprimer_dans_un_fichier.print_bgcolor
false
print.printer_Imprimer_dans_un_fichier.print_bgimages
false
print.printer_Imprimer_dans_un_fichier.print_colorspace
default
print.printer_Imprimer_dans_un_fichier.print_command
lpr $
print.printer_Imprimer_dans_un_fichier.print_downloadfonts
false
print.printer_Imprimer_dans_un_fichier.print_edge_bottom
0
print.printer_Imprimer_dans_un_fichier.print_edge_left
0
print.printer_Imprimer_dans_un_fichier.print_edge_right
0
print.printer_Imprimer_dans_un_fichier.print_edge_top
0
print.printer_Imprimer_dans_un_fichier.print_evenpages
true
print.printer_Imprimer_dans_un_fichier.print_footercenter
print.printer_Imprimer_dans_un_fichier.print_footerleft
&PT
print.printer_Imprimer_dans_un_fichier.print_footerright
&D
print.printer_Imprimer_dans_un_fichier.print_headercenter
print.printer_Imprimer_dans_un_fichier.print_headerleft
&T
print.printer_Imprimer_dans_un_fichier.print_headerright
&U
print.printer_Imprimer_dans_un_fichier.print_in_color
true
print.printer_Imprimer_dans_un_fichier.print_margin_bottom
0.500000012107193
print.printer_Imprimer_dans_un_fichier.print_margin_left
0.500000012107193
print.printer_Imprimer_dans_un_fichier.print_margin_right
0.500000012107193
print.printer_Imprimer_dans_un_fichier.print_margin_top
0.500000012107193
print.printer_Imprimer_dans_un_fichier.print_oddpages
true
print.printer_Imprimer_dans_un_fichier.print_orientation
0
print.printer_Imprimer_dans_un_fichier.print_pagedelay
500
print.printer_Imprimer_dans_un_fichier.print_paper_data
0
print.printer_Imprimer_dans_un_fichier.print_paper_height
279,40
print.printer_Imprimer_dans_un_fichier.print_paper_name
A4
print.printer_Imprimer_dans_un_fichier.print_paper_size_type
1
print.printer_Imprimer_dans_un_fichier.print_paper_size_unit
1
print.printer_Imprimer_dans_un_fichier.print_paper_width
215,90
print.printer_Imprimer_dans_un_fichier.print_plex_name
default
print.printer_Imprimer_dans_un_fichier.print_resolution_name
default
print.printer_Imprimer_dans_un_fichier.print_reversed
false
print.printer_Imprimer_dans_un_fichier.print_scaling
1,00
print.printer_Imprimer_dans_un_fichier.print_shrink_to_fit
true
print.printer_Imprimer_dans_un_fichier.print_to_file
false
print.printer_Imprimer_dans_un_fichier.print_unwriteable_margin_bottom
56
print.printer_Imprimer_dans_un_fichier.print_unwriteable_margin_left
25
print.printer_Imprimer_dans_un_fichier.print_unwriteable_margin_right
25
print.printer_Imprimer_dans_un_fichier.print_unwriteable_margin_top
25
print.printer_couleur.print_bgcolor
true
print.printer_couleur.print_bgimages
true
print.printer_couleur.print_colorspace
default
print.printer_couleur.print_command
lpr $
print.printer_couleur.print_downloadfonts
false
print.printer_couleur.print_edge_bottom
0
print.printer_couleur.print_edge_left
0
print.printer_couleur.print_edge_right
0
print.printer_couleur.print_edge_top
0
print.printer_couleur.print_evenpages
true
print.printer_couleur.print_footercenter
print.printer_couleur.print_footerleft
&PT
print.printer_couleur.print_footerright
&D
print.printer_couleur.print_headercenter
print.printer_couleur.print_headerleft
&T
print.printer_couleur.print_headerright
&U
print.printer_couleur.print_in_color
true
print.printer_couleur.print_margin_bottom
0.500000012107193
print.printer_couleur.print_margin_left
0.500000012107193
print.printer_couleur.print_margin_right
0.500000012107193
print.printer_couleur.print_margin_top
0.500000012107193
print.printer_couleur.print_oddpages
true
print.printer_couleur.print_orientation
0
print.printer_couleur.print_pagedelay
500
print.printer_couleur.print_paper_data
0
print.printer_couleur.print_paper_height
279,40
print.printer_couleur.print_paper_name
A4
print.printer_couleur.print_paper_size_type
1
print.printer_couleur.print_paper_size_unit
1
print.printer_couleur.print_paper_width
215,90
print.printer_couleur.print_plex_name
default
print.printer_couleur.print_resolution_name
default
print.printer_couleur.print_reversed
false
print.printer_couleur.print_scaling
1,00
print.printer_couleur.print_shrink_to_fit
true
print.printer_couleur.print_to_file
false
print.printer_couleur.print_unwriteable_margin_bottom
56
print.printer_couleur.print_unwriteable_margin_left
25
print.printer_couleur.print_unwriteable_margin_right
25
print.printer_couleur.print_unwriteable_margin_top
25
print.printer_laser.print_bgcolor
false
print.printer_laser.print_bgimages
false
print.printer_laser.print_colorspace
default
print.printer_laser.print_command
lpr $
print.printer_laser.print_downloadfonts
false
print.printer_laser.print_edge_bottom
0
print.printer_laser.print_edge_left
0
print.printer_laser.print_edge_right
0
print.printer_laser.print_edge_top
0
print.printer_laser.print_evenpages
true
print.printer_laser.print_footercenter
print.printer_laser.print_footerleft
&PT
print.printer_laser.print_footerright
&D
print.printer_laser.print_headercenter
print.printer_laser.print_headerleft
&T
print.printer_laser.print_headerright
&U
print.printer_laser.print_in_color
true
print.printer_laser.print_margin_bottom
0.500000012107193
print.printer_laser.print_margin_left
0.500000012107193
print.printer_laser.print_margin_right
0.500000012107193
print.printer_laser.print_margin_top
0.500000012107193
print.printer_laser.print_oddpages
true
print.printer_laser.print_orientation
0
print.printer_laser.print_pagedelay
500
print.printer_laser.print_paper_data
0
print.printer_laser.print_paper_height
279,40
print.printer_laser.print_paper_name
A4
print.printer_laser.print_paper_size_type
1
print.printer_laser.print_paper_size_unit
1
print.printer_laser.print_paper_width
215,90
print.printer_laser.print_plex_name
default
print.printer_laser.print_resolution_name
default
print.printer_laser.print_reversed
false
print.printer_laser.print_scaling
1,00
print.printer_laser.print_shrink_to_fit
true
print.printer_laser.print_to_file
false
print.printer_laser.print_unwriteable_margin_bottom
56
print.printer_laser.print_unwriteable_margin_left
25
print.printer_laser.print_unwriteable_margin_right
25
print.printer_laser.print_unwriteable_margin_top
25
print.tmp.printerfeatures.CUPS/laser.can_change_colorspace
false
print.tmp.printerfeatures.CUPS/laser.can_change_downloadfonts
false
print.tmp.printerfeatures.CUPS/laser.can_change_jobtitle
false
print.tmp.printerfeatures.CUPS/laser.can_change_num_copies
true
print.tmp.printerfeatures.CUPS/laser.can_change_orientation
true
print.tmp.printerfeatures.CUPS/laser.can_change_paper_size
true
print.tmp.printerfeatures.CUPS/laser.can_change_plex
false
print.tmp.printerfeatures.CUPS/laser.can_change_printincolor
true
print.tmp.printerfeatures.CUPS/laser.can_change_resolution
false
print.tmp.printerfeatures.CUPS/laser.can_change_spoolercommand
false
print.tmp.printerfeatures.CUPS/laser.colorspace.0.name
default
print.tmp.printerfeatures.CUPS/laser.colorspace.count
1
print.tmp.printerfeatures.CUPS/laser.has_special_printerfeatures
true
print.tmp.printerfeatures.CUPS/laser.orientation.0.name
portrait
print.tmp.printerfeatures.CUPS/laser.orientation.1.name
landscape
print.tmp.printerfeatures.CUPS/laser.orientation.count
2
print.tmp.printerfeatures.CUPS/laser.paper.0.height_mm
210
print.tmp.printerfeatures.CUPS/laser.paper.0.is_inch
false
print.tmp.printerfeatures.CUPS/laser.paper.0.name
A5
print.tmp.printerfeatures.CUPS/laser.paper.0.width_mm
148
print.tmp.printerfeatures.CUPS/laser.paper.1.height_mm
297
print.tmp.printerfeatures.CUPS/laser.paper.1.is_inch
false
print.tmp.printerfeatures.CUPS/laser.paper.1.name
A4
print.tmp.printerfeatures.CUPS/laser.paper.1.width_mm
210
print.tmp.printerfeatures.CUPS/laser.paper.2.height_mm
420
print.tmp.printerfeatures.CUPS/laser.paper.2.is_inch
false
print.tmp.printerfeatures.CUPS/laser.paper.2.name
A3
print.tmp.printerfeatures.CUPS/laser.paper.2.width_mm
297
print.tmp.printerfeatures.CUPS/laser.paper.3.height_mm
279
print.tmp.printerfeatures.CUPS/laser.paper.3.is_inch
true
print.tmp.printerfeatures.CUPS/laser.paper.3.name
Letter
print.tmp.printerfeatures.CUPS/laser.paper.3.width_mm
215
print.tmp.printerfeatures.CUPS/laser.paper.4.height_mm
355
print.tmp.printerfeatures.CUPS/laser.paper.4.is_inch
true
print.tmp.printerfeatures.CUPS/laser.paper.4.name
Legal
print.tmp.printerfeatures.CUPS/laser.paper.4.width_mm
215
print.tmp.printerfeatures.CUPS/laser.paper.5.height_mm
431
print.tmp.printerfeatures.CUPS/laser.paper.5.is_inch
true
print.tmp.printerfeatures.CUPS/laser.paper.5.name
Tabloid
print.tmp.printerfeatures.CUPS/laser.paper.5.width_mm
279
print.tmp.printerfeatures.CUPS/laser.paper.6.height_mm
254
print.tmp.printerfeatures.CUPS/laser.paper.6.is_inch
true
print.tmp.printerfeatures.CUPS/laser.paper.6.name
Executive
print.tmp.printerfeatures.CUPS/laser.paper.6.width_mm
190
print.tmp.printerfeatures.CUPS/laser.paper.count
7
print.tmp.printerfeatures.CUPS/laser.plex.0.name
default
print.tmp.printerfeatures.CUPS/laser.plex.count
1
print.tmp.printerfeatures.CUPS/laser.resolution.0.name
default
print.tmp.printerfeatures.CUPS/laser.resolution.count
1
print.tmp.printerfeatures.CUPS/laser.supports_colorspace_change
false
print.tmp.printerfeatures.CUPS/laser.supports_downloadfonts_change
false
print.tmp.printerfeatures.CUPS/laser.supports_jobtitle_change
false
print.tmp.printerfeatures.CUPS/laser.supports_orientation_change
true
print.tmp.printerfeatures.CUPS/laser.supports_paper_size_change
true
print.tmp.printerfeatures.CUPS/laser.supports_plex_change
false
print.tmp.printerfeatures.CUPS/laser.supports_printincolor_change
true
print.tmp.printerfeatures.CUPS/laser.supports_resolution_change
false
print.tmp.printerfeatures.CUPS/laser.supports_spoolercommand_change
false
print.tmp.printerfeatures.laser.can_change_colorspace
false
print.tmp.printerfeatures.laser.can_change_downloadfonts
false
print.tmp.printerfeatures.laser.can_change_jobtitle
false
print.tmp.printerfeatures.laser.can_change_num_copies
true
print.tmp.printerfeatures.laser.can_change_orientation
true
print.tmp.printerfeatures.laser.can_change_paper_size
true
print.tmp.printerfeatures.laser.can_change_plex
false
print.tmp.printerfeatures.laser.can_change_printincolor
true
print.tmp.printerfeatures.laser.can_change_resolution
false
print.tmp.printerfeatures.laser.can_change_spoolercommand
false
print.tmp.printerfeatures.laser.colorspace.0.name
default
print.tmp.printerfeatures.laser.colorspace.count
1
print.tmp.printerfeatures.laser.has_special_printerfeatures
true
print.tmp.printerfeatures.laser.orientation.0.name
portrait
print.tmp.printerfeatures.laser.orientation.1.name
landscape
print.tmp.printerfeatures.laser.orientation.count
2
print.tmp.printerfeatures.laser.paper.0.height_mm
210
print.tmp.printerfeatures.laser.paper.0.is_inch
false
print.tmp.printerfeatures.laser.paper.0.name
A5
print.tmp.printerfeatures.laser.paper.0.width_mm
148
print.tmp.printerfeatures.laser.paper.1.height_mm
297
print.tmp.printerfeatures.laser.paper.1.is_inch
false
print.tmp.printerfeatures.laser.paper.1.name
A4
print.tmp.printerfeatures.laser.paper.1.width_mm
210
print.tmp.printerfeatures.laser.paper.2.height_mm
420
print.tmp.printerfeatures.laser.paper.2.is_inch
false
print.tmp.printerfeatures.laser.paper.2.name
A3
print.tmp.printerfeatures.laser.paper.2.width_mm
297
print.tmp.printerfeatures.laser.paper.3.height_mm
279
print.tmp.printerfeatures.laser.paper.3.is_inch
true
print.tmp.printerfeatures.laser.paper.3.name
Letter
print.tmp.printerfeatures.laser.paper.3.width_mm
215
print.tmp.printerfeatures.laser.paper.4.height_mm
355
print.tmp.printerfeatures.laser.paper.4.is_inch
true
print.tmp.printerfeatures.laser.paper.4.name
Legal
print.tmp.printerfeatures.laser.paper.4.width_mm
215
print.tmp.printerfeatures.laser.paper.5.height_mm
431
print.tmp.printerfeatures.laser.paper.5.is_inch
true
print.tmp.printerfeatures.laser.paper.5.name
Tabloid
print.tmp.printerfeatures.laser.paper.5.width_mm
279
print.tmp.printerfeatures.laser.paper.6.height_mm
254
print.tmp.printerfeatures.laser.paper.6.is_inch
true
print.tmp.printerfeatures.laser.paper.6.name
Executive
print.tmp.printerfeatures.laser.paper.6.width_mm
190
print.tmp.printerfeatures.laser.paper.count
7
print.tmp.printerfeatures.laser.plex.0.name
default
print.tmp.printerfeatures.laser.plex.count
1
print.tmp.printerfeatures.laser.resolution.0.name
default
print.tmp.printerfeatures.laser.resolution.count
1
print.tmp.printerfeatures.laser.supports_colorspace_change
false
print.tmp.printerfeatures.laser.supports_downloadfonts_change
false
print.tmp.printerfeatures.laser.supports_jobtitle_change
false
print.tmp.printerfeatures.laser.supports_orientation_change
true
print.tmp.printerfeatures.laser.supports_paper_size_change
true
print.tmp.printerfeatures.laser.supports_plex_change
false
print.tmp.printerfeatures.laser.supports_printincolor_change
true
print.tmp.printerfeatures.laser.supports_resolution_change
false
print.tmp.printerfeatures.laser.supports_spoolercommand_change
false
privacy.clearOnShutdown.cookies
false
privacy.cpd.cookies
true
privacy.sanitize.migrateFx3Prefs
true
privacy.sanitize.promptOnSanitize
false
privacy.sanitize.sanitizeOnShutdown
true
privacy.sanitize.timeSpan
0
security.disable_button.openCertManager
false
security.enable_tls_session_tickets
false
security.warn_viewing_mixed
false

Morbus 135 solutions 2340 answers

Issues of this sort are, unfortunately, more common and the we'd like them to be. However, they tend not to be cause by Firefox itself, but rather by software that is running either inside or alongside it, such as add-ons or firewalls. Since these issues have a broad span of possible causes, you need to diagnose your problems before fixing them. Follow these instructions to the line, as they'll probably help you diagnose and fix the problems you're having.

  1. run Firefox in safe-mode to disable all extensions, themes and plugins. If this fixes your problem, be it with RAM or CPU usage, then you know it's a problem with add-ons (plugins, themes or extensions). Proceed to number 2. If safe-mode doesn't fix your problem, then read bellow, after this list;
  2. update all extensions (go into Tools > Add-ons > Extensions > Find Updates), themes and plugins (see this page in your Firefox. If this doesn't solve the issues, proceed to the following number;
  3. disable all extensions, themes and plugins in your Firefox (not running safe-mode). This is temporary and for diagnostic purposes only. Being certain that, as in safe-mode, the problems you're having have gone away, enable one plugin at a time. You should be certain that you actually want that plugin to be enabled. It's best to keep the overall number of enabled plugins as low as possible. When you encounter problems, you know you've found a problematic plugin, so disable it for good. Keep enabling all plugins (except problematic ones) until you've gone through them all. If you need support for a problematic plugin, you need to contact its author for support;
  4. enable one extension at a time. Again, be certain that you actually want that extension to be enabled. As with plguins, it's best to keep the overall number of enabled extensions as low as possible. Also, try the theme you want to have installed so see if that is what's causing the problem. When you encounter problems, you know you've found a problematic extension/theme, so disable it for good. Keep enabling all your extensions (except problematic ones) until you've gone through them all. Just the same as with plugins, if you need support for a problematic extension/plugin, you need to contact its author;
  5. if you've followed my instructions above, you're done! You've fixed your problems with problematic add-ons. If you want to keep using those problematic add-ons, please contant their authors for support.

Ok, now... If disabling all extensions and plugins through safe-mode didn't work to fix your problems (or, in other words, if you've just read number 1 on the list above and come straight here), then you have different issue. The most likely scenario is that you have a third party software running on your computer that is messing with Firefox. Detecting which program it is may be tricky, but the following list should help you. Make sure you follow it carefully. Don't forget to answer the question on the last point, if nothing else helps.

  1. try reinstalling Firefox. No data will be lost. You can get the latest version (for free, as always) at getfirefox.com. Make sure you uninstall Firefox prior to reinstalling it. For help installing Firefox, see this support article. If that doesn't fix the problem, proceed;
  2. do a virus/malware check on your computer. See this support article for help on this point. This is a very important step, so please pay attention to it. If your problem is not due to viruses/malware, proceed;
  3. disable all software running in the background that you don't want to have running in the background (in Windows operating systems, this is done by pressing WINDOWS+R in your keyboard, typing msconfig and pressing Enter; now, under the Startup tab, you can uncheck the software you don't want, and reboot your system for changes to take effect; if you're unsure of what software you want running, ask someone with more experience). If this doesn't fix your issues with Firefox, proceed;
  4. check if your firewall/antivirus/security suite is conflicting in any way with Firefox's normal behavior. Check for enabled functions/features that you don't want and/or may be causing problems with Firefox. You'll find that these features are most likely tied to Internet Security features, such as link scanners or URL checkers and the like. If you're not sure they are conflicting with Firefox, simply try to disable them temporarily to see whether or not that's true. If this doesn't solve the issues, proceed to the following number;
  5. check your operating system security options, mainly advanced options that are not configured by default. While it's very unlikely that this may be the cause of the problem, it's remotely possible. If this doesn't work, proceed to the following point;
  6. update your modem/router software. There have been some reports that some modem/router software may cause Firefox and other browsers to loose performance and/or stability. If updating doesn't fix your issue, try other versions of the software, if possible. If you need support with this, contact your modem/router manufacturer. If this doesn't help, proceed;
  7. if you are using a Windows operating system, clean up your OS registry using appropriate software. There have been reports that badly maintained Windows Registries may case problems with Firefox. If this doesn't help, see the following point;
  8. please try creating a new temporary Firefox profile (managing profiles) and see if the issues persist. Please report the results, so we can help you further.
Issues of this sort are, unfortunately, more common and the we'd like them to be. However, they tend not to be cause by Firefox itself, but rather by software that is running either inside or alongside it, such as add-ons or firewalls. Since these issues have a broad span of possible causes, you need to diagnose your problems before fixing them. Follow these instructions ''to the line'', as they'll probably help you diagnose and fix the problems you're having. #run Firefox in [http://support.mozilla.com/en-US/kb/Safe+Mode safe-mode] to disable all extensions, themes and plugins. If this fixes your problem, be it with RAM or CPU usage, then you know it's a problem with add-ons (plugins, themes or extensions). Proceed to number 2. If safe-mode doesn't fix your problem, then read bellow, after this list; #update all extensions (go into ''Tools > Add-ons > Extensions > Find Updates''), themes and plugins (see [https://www.mozilla.com/en-US/plugincheck/ this page] in your Firefox. If this doesn't solve the issues, proceed to the following number; #disable all extensions, themes and plugins in your Firefox (not running safe-mode). This is temporary and for diagnostic purposes only. Being certain that, as in safe-mode, the problems you're having have gone away, enable one plugin at a time. You should be certain that you actually want that plugin to be enabled. It's best to keep the overall number of enabled plugins as low as possible. When you encounter problems, you know you've found a problematic plugin, so disable it for good. Keep enabling all plugins (except problematic ones) until you've gone through them all. If you need support for a problematic plugin, you need to contact its author for support; #enable one extension at a time. Again, be certain that you actually want that extension to be enabled. As with plguins, it's best to keep the overall number of enabled extensions as low as possible. Also, try the theme you want to have installed so see if that is what's causing the problem. When you encounter problems, you know you've found a problematic extension/theme, so disable it for good. Keep enabling all your extensions (except problematic ones) until you've gone through them all. Just the same as with plugins, if you need support for a problematic extension/plugin, you need to contact its author; #if you've followed my instructions above, you're done! You've fixed your problems with problematic add-ons. If you want to keep using those problematic add-ons, please contant their authors for support. Ok, now... ''If'' disabling all extensions and plugins through safe-mode didn't work to fix your problems (or, in other words, if you've just read number 1 on the list above and come straight here), then you have different issue. The most likely scenario is that you have a third party software running on your computer that is messing with Firefox. Detecting which program it is may be tricky, but the following list should help you. Make sure you follow it carefully. Don't forget to answer the question on the last point, if nothing else helps. #try reinstalling Firefox. No data will be lost. You can get the latest version (for free, as always) at [http://www.getfirefox.com/ getfirefox.com]. Make sure you [http://support.mozilla.com/en-US/kb/Uninstalling+Firefox uninstall Firefox] prior to reinstalling it. For help installing Firefox, see [https://support.mozilla.com/en-US/kb/Installing+Firefox this support article]. If that doesn't fix the problem, proceed; #do a virus/malware check on your computer. See [https://support.mozilla.com/en-US/kb/Is+my+Firefox+problem+a+result+of+malware?s=malware&as=s this support article] for help on this point. ''This is a very important step'', so please pay attention to it. If your problem is not due to viruses/malware, proceed; #disable all software running in the background that you don't want to have running in the background (in Windows operating systems, this is done by pressing WINDOWS+R in your keyboard, typing ''msconfig'' and pressing Enter; now, under the ''Startup'' tab, you can uncheck the software you don't want, and reboot your system for changes to take effect; if you're unsure of what software you want running, ask someone with more experience). If this doesn't fix your issues with Firefox, proceed; #check if your firewall/antivirus/security suite is conflicting in any way with Firefox's normal behavior. Check for enabled functions/features that you don't want and/or may be causing problems with Firefox. You'll find that these features are most likely tied to Internet Security features, such as link scanners or URL checkers and the like. If you're not sure they are conflicting with Firefox, simply try to disable them temporarily to see whether or not that's true. If this doesn't solve the issues, proceed to the following number; #check your operating system security options, mainly advanced options that are not configured by default. While it's very unlikely that this may be the cause of the problem, it's remotely possible. If this doesn't work, proceed to the following point; #update your modem/router software. There have been some reports that some modem/router software may cause Firefox and other browsers to loose performance and/or stability. If updating doesn't fix your issue, try other versions of the software, if possible. If you need support with this, contact your modem/router manufacturer. If this doesn't help, proceed; #if you are using a Windows operating system, clean up your OS registry using appropriate software. There have been reports that badly maintained Windows Registries may case problems with Firefox. If this doesn't help, see the following point; #please try creating a new temporary Firefox profile ([http://support.mozilla.com/en-US/kb/Managing+profiles managing profiles]) and see if the issues persist. Please report the results, so we can help you further.