ZyXEL Communications USG40 User Manual page 502

Chapter 30 SSL Inspection
30.3.1.1 Firefox Browser
If you're using a Firefox browser, in addition to the above you need to do the following to import a
certificate into the browser.
Click Tools > Options > Advanced > Encryption > View Certificates, click Import and enter
the filename of the certificate you want to import. See the browser's help for further information.
ZyWALL/USG Series User's Guide
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