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With Firefox, when I start Facebook, all of a sudden it comes up as a page full of gibberish, no graphics etc. What could have happened?

  • 3 replies
  • 2 have this problem
  • 8 views
  • Last reply by cor-el

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Chosen solution

Hey there rlowe, we are currently aware of this issue and the problem lies with Kaspersky.

Please go here to attempt to correct the issue: https://support.mozilla.org/en-US/kb/troubleshoot-SEC_ERROR_UNKNOWN_ISSUER#w_kaspersky

Sincerely, Kyle

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Chosen Solution

Hey there rlowe, we are currently aware of this issue and the problem lies with Kaspersky.

Please go here to attempt to correct the issue: https://support.mozilla.org/en-US/kb/troubleshoot-SEC_ERROR_UNKNOWN_ISSUER#w_kaspersky

Sincerely, Kyle

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Thank-you for you time in helping me solve this issue...Have a blessed day...

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See also:

Facebook appears to have enabled Brotli (br) encoding for secure connections and Kapsersky doesn't know about this encoding and strips it from the HTTP response headers.

A possible workaround is to modify the involved pref and remove the trailing ", br"

  • 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.

Modified by cor-el