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Proxy/VPN extensions have stopped working

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So, on my Firefox setup I use two extensions to circumvent website blocking in my country - one is an extension to make a specific website always available. The other is AnonymoX which I use for general purposes.

A few days ago I upgraded to Firefox 71.0 as well as updated my Windows 10 to the latest 1903 version. Today I noticed that both extensions have stopped working. AnonymoX just doesn't work, whereas the other plugin, upon activation, says (translated) "Conflict detected! Proxy settings are controlled by a different plugin or cannot be set up" Trying to circumvent a block (and only then - unblocked websites work fine) now either redirects me to the ISPs blocking page, or alternatively produces a "Secure Connection Failed PR_END_OF_FILE_ERROR" message after a long TLS handshake. Running the same extensions in Chrome does not reproduce the issue - blocked websites become accessible as usual. The issue also persists for three different connections - a public wi-fi network, a private network and a tethered 4G connection, all served by different ISPs. Finally, I am not running any anti-virus software or firewall. Thus this seems to be a Firefox issue and not a system or network issue.

This also doesn't seem to be an issue with the country's blocking system itself because other users around me are still able to circumvent blocks using the same extensions and I am able to circumvent blocks using a similar extension on my Android phone with a local SIM.

Things I've tried so far: 1) Made sure that both Windows and Firefox are set to not use a proxy

2) Reinstalled the extensions

3) Created a different profile in Firefox. The extensions don't work in the new profile either, although the PR_END_OF_FILE_ERROR does not appear - I just always get redirected to the respective ISPs block page

4) Cleared all cache, cookies, site settings etc.

5) Deleted the cert9.db file and let Firefox recereate it

So far nothing has worked. I'm frankly at a loss here. I have half a mind to just reinstall Firefox altogether since this is not my main PC and losing bookmarks wouldn't inconvenience me on it, but figured I'd ask here before.

So, on my Firefox setup I use two extensions to circumvent website blocking in my country - one is an extension to make a specific website always available. The other is AnonymoX which I use for general purposes. A few days ago I upgraded to Firefox 71.0 as well as updated my Windows 10 to the latest 1903 version. Today I noticed that both extensions have stopped working. AnonymoX just doesn't work, whereas the other plugin, upon activation, says (translated) "Conflict detected! Proxy settings are controlled by a different plugin or cannot be set up" Trying to circumvent a block (and only then - unblocked websites work fine) now either redirects me to the ISPs blocking page, or alternatively produces a "Secure Connection Failed PR_END_OF_FILE_ERROR" message after a long TLS handshake. Running the same extensions in Chrome does not reproduce the issue - blocked websites become accessible as usual. The issue also persists for three different connections - a public wi-fi network, a private network and a tethered 4G connection, all served by different ISPs. Finally, I am not running any anti-virus software or firewall. Thus this seems to be a Firefox issue and not a system or network issue. This also doesn't seem to be an issue with the country's blocking system itself because other users around me are still able to circumvent blocks using the same extensions and I am able to circumvent blocks using a similar extension on my Android phone with a local SIM. Things I've tried so far: 1) Made sure that both Windows and Firefox are set to not use a proxy 2) Reinstalled the extensions 3) Created a different profile in Firefox. The extensions don't work in the new profile either, although the PR_END_OF_FILE_ERROR does not appear - I just always get redirected to the respective ISPs block page 4) Cleared all cache, cookies, site settings etc. 5) Deleted the cert9.db file and let Firefox recereate it So far nothing has worked. I'm frankly at a loss here. I have half a mind to just reinstall Firefox altogether since this is not my main PC and losing bookmarks wouldn't inconvenience me on it, but figured I'd ask here before.

Modified by nlkonovalenko

Chosen solution

hi, firefox 71 contained some changes in the proxy API for webextensions: https://bugzilla.mozilla.org/show_bug.cgi?id=1443259

so it's most likely they'd need to adapt. you could look into the version changelog of the addons you're using on addons.mozilla.org and if there weren't any updates in the past couple of weeks you might need to get in contact with their support and ask them to adapt and update...

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All Replies (2)

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Chosen Solution

hi, firefox 71 contained some changes in the proxy API for webextensions: https://bugzilla.mozilla.org/show_bug.cgi?id=1443259

so it's most likely they'd need to adapt. you could look into the version changelog of the addons you're using on addons.mozilla.org and if there weren't any updates in the past couple of weeks you might need to get in contact with their support and ask them to adapt and update...

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Hi philipp and thank you for the quick reply!

AnonymoX has not been updated since 71.0. However, the other extension has apparently been rereleased under a different name quite some time ago and is being actively maintained. Installing the latest version has resolved the issue.

Again, thanks!