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Extension blocklisting on Firefox is no longer working, what should I do?

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I noticed that the extension blocklisting is no longer working on Firefox. I checked the extension.blocklist options in about:config and all of them are set to the default values. My other laptop still has the extension blocklist working, but the one I'm using doesn't. Does anyone know which files are associated with extension blocklisting? 'Cause I want to be sure that the extension blocklist is working, just incase I download a malicious add-on or extension. I already have two add-ons that are on the blocklist, but Firefox isn't blocking them, which are: MetaStream 3 Plugin 3.2.2.26 and McAfee SiteAdvisor 3.4.1.123

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Nevermind, I've fixed the issue. There were some faulty files in AppData\Roaming\Mozilla\Firefox\Profiles\nuutfn45.default\

The following files were faulty:

Name: blocklist.xml Issue: It had less blocklisted plugins than other ones, MetaStream 3 Plugin 3.2.2.26 was not listed in the blocklist.xml and it did not display the warning "MetaStream 3 Plugin has been disabled due to security or stability issues." Blocklist.xml also puts in entries into pluginreg.dat to tell Firefox which add-ons to remove the enable/disable button, which is normal. But if the add-on isn't listed, then the entry in pluginreg.dat will show the enable/disable button.

Name: pluginreg.dat Issue: This plugin didn't remove the enable/disable button on a blocklisted plugin like it normally should, so I could enable the MetaStream 3 Plugin whenever I wished to.

Name: pluginreg.dat.bak Issue: This file is a backup of the faulty pluginreg.dat file


So if anyone has a problem with blocklisting not being enabled like it should, then delete the files that I have listed above.

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Chosen Solution

Nevermind, I've fixed the issue. There were some faulty files in AppData\Roaming\Mozilla\Firefox\Profiles\nuutfn45.default\

The following files were faulty:

Name: blocklist.xml Issue: It had less blocklisted plugins than other ones, MetaStream 3 Plugin 3.2.2.26 was not listed in the blocklist.xml and it did not display the warning "MetaStream 3 Plugin has been disabled due to security or stability issues." Blocklist.xml also puts in entries into pluginreg.dat to tell Firefox which add-ons to remove the enable/disable button, which is normal. But if the add-on isn't listed, then the entry in pluginreg.dat will show the enable/disable button.

Name: pluginreg.dat Issue: This plugin didn't remove the enable/disable button on a blocklisted plugin like it normally should, so I could enable the MetaStream 3 Plugin whenever I wished to.

Name: pluginreg.dat.bak Issue: This file is a backup of the faulty pluginreg.dat file


So if anyone has a problem with blocklisting not being enabled like it should, then delete the files that I have listed above.