Please explain the problem in detail. What happens? What is/are the exact error message(s) ?

Make sure you are not blocking content.

https://support.mozilla.org/en-US/kb/enhanced-tracking-protection-firefox-desktop also see https://blog.mozilla.org/security/2021/03/23/introducing-smartblock/

https://support.mozilla.org/en-US/kb/smartblock-enhanced-tracking-protection

Diagnose Firefox issues using Troubleshoot(Safe) Mode {web link}

A small dialog should appear. Click Start In Troubleshoot(Safe) Mode (not Refresh). Is the problem still there?

Many site issues can be caused by corrupt cookies or cache.

Warning ! ! This will log you out of sites you're logged in to. You may also lose any settings for that website.

• Delete cookies to remove the information websites have stored on your computer {web link}

• How to clear the Firefox cache {web link}

Here is the fix

1. Open a tab and type about:config in the address bar. 2. Once in, type ocsp in the config search bar. 3. Toggle the parameter security.ssl.enable_ocsp_stapling from true to false

Related bug (should be fixed soon) Bug 1745600 MOZILLA_PKIX_ERROR_OCSP_RESPONSE_FOR_CERT_MISSING on some Microsoft sites

P.S. You should not set security.ssl.enable_ocsp_stapling to false as a workaround since this can make you less secure. You can use a different browser to access Microsoft websites until this bug is fixed.

Note that bug 966856 has been fixed for 95, 96, and 91 ESR, so now it is waiting for an update getting released.

• https://support.mozilla.org/en-US/forums/contributors/715454?last=82524#post-82524

This bug is fixed in Firefox 95.0.1 so you should update Firefox to the latest release.

If you disabled ocsp stapling in about:config as a workaround, please reset this preference to 'true.