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Get gibberish when trying to login to Facebook. I am not running Kapersky. Firefox 46.0.1 and Windows 7 are what I'm running. Cleared cache and cookies.

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  • Last reply by James

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I cleared the cache and cookies multiple times but it doesn't fix the problem. Sometimes the gibberish appears when I connect to Facebook. Other times the login screen will appear but when I login the gibberish appears. It's the same gibberish as others got who were running Kapersky. I run Microsoft Security Essentials and MacAfee Security Scan Plus. I'm able to login to Facebook using Internet Explorer. I've attached a screen print showing what the gibberish for Facebook page looks like.

The Java Deployment Toolkit 6.0.220.4 plug-in is disabled because Firefox disabled it for vulnerability reasons.

I cleared the cache and cookies multiple times but it doesn't fix the problem. Sometimes the gibberish appears when I connect to Facebook. Other times the login screen will appear but when I login the gibberish appears. It's the same gibberish as others got who were running Kapersky. I run Microsoft Security Essentials and MacAfee Security Scan Plus. I'm able to login to Facebook using Internet Explorer. I've attached a screen print showing what the gibberish for Facebook page looks like. The Java Deployment Toolkit 6.0.220.4 plug-in is disabled because Firefox disabled it for vulnerability reasons.

Chosen solution

If you use Kaspersky software then make sure you have the latest updates.

Firefox 44+ accepts a new kind of encoding (compression) called Brotli (br) for secure connections. Facebook appears to have enabled Brotli (br) encoding for secure connections recently. Kaspersky didn't know about this encoding and strips it from the HTTP response headers if "Inject script" is checked, but there has been an update released by Kaspersky to address this issue, so make sure you have the latest Kaspersky updates.


If this doesn't apply then a possible workaround is to modify the involved pref and remove the trailing ", br" to prevent the server from sending files with Brotli compression.

network.http.accept-encoding.secure = "gzip, deflate, br" => "gzip, deflate" (without quotes)

You can open the about:config page via the location/address bar. You can accept the warning and click "I'll be careful" to continue.

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Seçilmiş Həll

If you use Kaspersky software then make sure you have the latest updates.

Firefox 44+ accepts a new kind of encoding (compression) called Brotli (br) for secure connections. Facebook appears to have enabled Brotli (br) encoding for secure connections recently. Kaspersky didn't know about this encoding and strips it from the HTTP response headers if "Inject script" is checked, but there has been an update released by Kaspersky to address this issue, so make sure you have the latest Kaspersky updates.


If this doesn't apply then a possible workaround is to modify the involved pref and remove the trailing ", br" to prevent the server from sending files with Brotli compression.

network.http.accept-encoding.secure = "gzip, deflate, br" => "gzip, deflate" (without quotes)

You can open the about:config page via the location/address bar. You can accept the warning and click "I'll be careful" to continue.

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Thank you for the response. I removed the ", br" from network.http.accept-encoding.secure and I'm now able to login to Facebook again.

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If you do not have Kaspersky then what antivirus do you have as something is interfering must like Kaspersky did.

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I run MacAfee Security Scan Plus and Microsoft Security Essentials. I have fixed the problem by removing ", br" from network.http.accept-encoding.secure.

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That is not a fix but a workaround of a issue that does not exist in Firefox (in 44.0 to 46.0.1) as it works with the Facebook Brotli (br) encoding just fine.

On a slow tablet so I cannot really investigate at moment if either of those software can be doing a similar thing. Make sure they have recent updates.