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Facebook, twitter and even mozilla help page is showing in basic view without any images. Providing two sample screenshots. Please respond asap.

Facebook, twitter and even mozilla help page is showing in basic view without any images. Providing two sample screenshots. Please respond asap.

Chosen solution

Unfortunately, the screen shots did not upload. You can start a reply to your own question and use the Browse button below the box to attach the image files. Please cut out or blur out any sensitive information before uploading. Thanks.

Since you appear to use Avast, let me explore a possible explanation...

Have you experienced any secure certificate errors, for example the sec_error_bad_signature error code? If you have Firefox create an "exception" to trust a suspicious certificate, that only applies to the main server, and if the site gets its style sheets from a different secure server, then the page will appear unstyled.

The most common reason for getting "sec_error_bad_signature" on numerous sites seems to be the Avast Web Shield. Web Shield intercepts your browsing and filters it, but to filter secure sites, it presents "fake" certificates to Firefox. Avast should have set up Firefox to trust its fake certificates but that seems to fail on a regular basis.

To test this theory, try turning off scanning of encrypted sites. I saw these steps in another post:

  1. Open the Avast dashboard on the affected system.
  2. Select Settings from the left sidebar menu.
  3. Switch to Active Protection.
  4. Click on Customize next to Web Shield.
  5. Uncheck the "Enable HTTPS Scanning" option and click ok

If that resolves the issue, but you prefer to filter encrypted communications, you may need to import the Avast! signing certficate into Firefox's Certificate Manager, Authorities tab.

Skaityti atsakymą kartu su kontekstu 👍 1

All Replies (1)

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Chosen Solution

Unfortunately, the screen shots did not upload. You can start a reply to your own question and use the Browse button below the box to attach the image files. Please cut out or blur out any sensitive information before uploading. Thanks.

Since you appear to use Avast, let me explore a possible explanation...

Have you experienced any secure certificate errors, for example the sec_error_bad_signature error code? If you have Firefox create an "exception" to trust a suspicious certificate, that only applies to the main server, and if the site gets its style sheets from a different secure server, then the page will appear unstyled.

The most common reason for getting "sec_error_bad_signature" on numerous sites seems to be the Avast Web Shield. Web Shield intercepts your browsing and filters it, but to filter secure sites, it presents "fake" certificates to Firefox. Avast should have set up Firefox to trust its fake certificates but that seems to fail on a regular basis.

To test this theory, try turning off scanning of encrypted sites. I saw these steps in another post:

  1. Open the Avast dashboard on the affected system.
  2. Select Settings from the left sidebar menu.
  3. Switch to Active Protection.
  4. Click on Customize next to Web Shield.
  5. Uncheck the "Enable HTTPS Scanning" option and click ok

If that resolves the issue, but you prefer to filter encrypted communications, you may need to import the Avast! signing certficate into Firefox's Certificate Manager, Authorities tab.