Problematic Firefox Extentions
| Extension | Versions affected | Problem | Workaround | References |
|---|---|---|---|---|
| Adblock | All | Having the OBJ_TABS setting enabled has been known to interfere with the ActiveX plugin (if installed). It can cause the plugin to ignore its configuration and run any ActiveX control, instead of the controls it is restricted to. Such a situation could potentially be a big security risk. | If you have the ActiveX plugin, keep the Adblock OBJ_TABS setting disabled. A mozilla code fix for this issue is forthcoming. | [1] [2] |
| Having the OBJ_TABS setting enabled will interfere with the Java plugin. Java applets will not display unless this setting is disabled. | If you want Java applets to display, keep the Adblock OBJ_TABS setting disabled. | [3][4] | ||
| Having the OBJ_TABS setting enabled may interfere with the Flash Player 8.0 plugin. No Flash content will be displayed unless this setting is disabled. | If updating to Adblock 0.5.3.042 or later does not resolve the issue, keep the Adblock OBJ_TABS setting disabled. | [5] | ||
| Having the OBJ_TABS setting enabled may interfere with the Windows Media Player plugin. Player video and controls will not appear on page, but sometimes audio will still play. | If updating to Adblock 0.5.3.042 or later does not resolve the issue, keep the Adblock OBJ_TABS setting disabled. | [6] | ||
| Causes Google Gmail Chat to crash. | ? | [7] | ||
| Prior to 0.5.3.042 | Having the OBJ_TABS setting enabled interferes with the Quicktime plugin. Video playback will have sound but no video. | Update to Adblock 0.5.3.042 or later. | [8] [9] | |
| Prior to 0.5.3.042 | Causes Firefox to hog memory | Update to Adblock 0.5.3.042 or later. | [10] | |
| 0.5.2.039 | (Firefox 1.0.x) Tools -> Extensions window won’t open after using “de-install” in the Adblock options menu. | Adblock should be uninstalled in Firefox from the Tools -> Extensions window (start in Firefox Safe Mode if the Extensions window doesn’t open). | [11] [12] | |
| Prior to 0.7.0.2 | Having “Show tabs on Java and Flash” enabled may cause the ActiveX plugin (if installed) to ignore its configuration and run any ActiveX control, posing a security risk. | Update to version 0.7.0.2 or later | [13] [14] | |
| Prior to 0.7 | Leaks memory | Update to version 0.7 or later | [15] | |
| All | Delays release of memory caused by closing a tab | Uninstall AdBlock Plus and install AdBlock | [16] | |
| 0.6.4 and prior | New extensions will not install. Also occurs in version 0.6.4 if updated from an earlier version or if used together with the SessionSaver extension. | Uninstall, then (re)install version 0.6.4. Disable opening the Extensions window in the sidebar (Misc. -> Extensions -> Open in Sidebar). | [17] | |
| 0.17 | The “Block all embedded objects” preference is set to “Yes” by default, causing embedded media normally handled by plugins to disappear, including Flash content. Also interferes with the IE Tab extension. | Change the “Block all embedded objects” preference setting to “No”. | [19][20] | |
| Prior to 0.3.0 | Add Bookmark fails in Firefox | Update to version 0.3.0 | [21] | |
| 1.0.x | Hangs or slows down Firefox | Disable prefetching, select “Optimized” preset instead of “Turbo”. | [22] | |
| All | Changes made by extension can interfere with Web site access, and persist after extension is uninstalled. | Reset defaults or create a new profile. | [23] | |
| All | Memory leak when used in conjunction with FlashGot | Do not use both FlashGot and Filterset.G Updater together. | [24] | |
| All | NoScript blocks JavaScript, which is required by FlashBlock | Do not use both FlashBlock and NoScript together (NoScript includes Flash-blocking functionality) | [25] | |
| All | Memory leak when used in conjunction with Filterset.G Updater | Do not use both FlashGot and Filterset.G Updater together. | [26] | |
| Prior to 0.9.2? | Memory leak | Update or uninstall. There is an unconfirmed report that there is also a memory problem with version 0.9.3. | [27][28] | |
| All? | Causes a dialog to appear that says “A script on this page is causing mozilla to run slowly. If it continues to run, your computer may become unresponsive. Do you want to abort the script?” | Uninstall the Google Toolbar and use the unofficial Googlebar extension instead. | [29] | |
| Leaks memory | [30] | |||
| All | Causes excessive disk activity | Disable Google Safe Browsing | [31] | |
| All | Greasemonkey scripts do not work on sites blocked by NoScript | Set NoScript to allow JavaScript on sites you wish to use Greasemonkey scripts on. | [32] | |
| Prior to 0.6.3 | Window title doesn’t change when switching tabs | Upgrade to a newer version | [33] | |
| Prior to 0.3.5 | Major security flaw that could allow websites full access to your computer | Upgrade to a newer version | [34] | |
| ? | Causes “ReferenceError: JEvent is not defined” | Update to the latest version | [35] [36] | |
| All | Memory leak | Uninstall IE Tab and install IE View Lite | [37] | |
| 2.6 | Gray bar below the status bar with red arrow. | Uninstall Linky. | [38] | |
| 22 | Firefox may fail to open after installing or updating the SiteAdvisor extension, which also may be installed as part of a McAfee software suite. This SiteAdvisor support article describes the problem as a conflict between SiteAdvisor and automatic proxy configuration scripts in Firefox. | Either follow the workaround in the SiteAdvisor support article or end the firefox process that remains in memory, start Firefox in Safe Mode and uninstall via Tools -> Extensions. If SiteAdvisor is a McAfee suite component it can also be removed using the McAfee uninstaller. | [39] [40] | |
| 23 | Firefox may crash with an error in Jar50.dll after installing or updating the SiteAdvisor extension or McAfee component. | Uninstall the SiteAdvisor extension or, if SiteAdvisor is installed as part of a McAfee software suite, remove the SiteAdvisor component using the McAfee uninstaller. | [41] | |
| All | Causes an illegal operation in the Windows Media Player plugin if it is blocking JavaScript on a page with embedded Windows Media | Do not block websites that have embedded Windows Media if you want to be able to play the media | [42] [43] | |
| FlashBlock requires JavaScript to work to block flash ads | Do not use both FlashBlock and NoScript together (NoScript includes Flash-blocking functionality) | [44] | ||
| Greasemonkey scripts require JavaScript | Set NoScript to allow JavaScript on sites you wish to use Greasemonkey scripts on. | [45] | ||
| All since 1.1.0 | Java is blocked by default on untrusted sites | Uncheck “Forbid Java” in NoScript’s Advanced options or, in version 1.1.3 and later you can temporarily allow Java content by clicking on its placeholder. | [46] [47] | |
| Prior to 1.1.3.9 | Causes Firefox to hog memory | Update to 1.1.3.9 or later | [48] | |
|
“Numbered Links” |
All | Malware identifies itself as “Numbered Links”. The real Numbered Links extension is harmless. See this article for more information. | Uninstall the extension. Scan your system for viruses, particularly “FormSpy” and “Downloader-AXM”. | [49][50] |
| All | Replaces all words on webpages with asterisks (******) if set to “censure” words. | Uninstall ProCon, restart Firefox, reset ProCon preferences in about:config, restart Firefox, reinstall. | [51] | |
| All | Leaks memory | Uninstall SessionSaver and install Session Manager | [52] | |
| Version 0.2 | Causes “unresponsive script” dialog when uploading files | Downgrade to version 0.2d | [53] | |
| Prior to 1.9996 | Changes Firefox’s user-agent string and can make addons.mozilla.org think you have an older version of Firefox installed | Update to a newer version. | [54] | |
| Prior to 2.78 | Causes excessive CPU usage | Update to a newer version. | [55] | |
| All | Causes new Firefox windows to freeze for a few seconds | Disable SwitchProxy’s auto-update feature | [56] | |
| All | General slowdown, conflicts with other extensions, can cause Firefox to not work at all | Uninstall TBE, use Tab Mix or Tab Mix Plus instead | [57] | |
| All (for Firefox in some languages) | Puts a bar at the bottom of the screen which reads:
<button id=”catTabbedButton” label=”&tabprefs.label;” |
Uninstall TBP | [58] | |
| 1.2.8.4 | Puts a bar at the bottom of the screen which reads:
%tabprefsDTD; |
Uninstall TBP and install it directly from the author’s website | [59] [60] | |
| Prior to 1.2.8.2 | Pressing Ctrl+Enter in the address bar opens page in new tab instead of adding “www.” and “.com” to the address | Update to a newer version | [61] | |
| Pressing home button opens homepage in new tab | Update to a newer version | [62] | ||
| Prior to 0.6.2 | Leaks memory | Update to version 0.6.2 or later | [63] | |
| Prior to 0.6.4 | Reinstallation or update causes hangs | Uninstall previous version in safe mode before installing new version | [64] | |
| All | Software update screen on opening windows and downloading fiiles. | Uninstall VeryDelicious | [65] | |
| 2.0.0 | Update causes Firefox to freeze | Uninstall previous version in safe mode then install the updated version. | [66] |
