Telephony: Click to Dial | Override Add-on Signing

To enable click to dial on the most recent version of firefox, you need to override add-on signing (advanced users).

Firefox knowledge base tells you

"You can temporarily override the setting to enforce the add-on signing requirement by changing the preference xpinstall.signatures.required to false in the Firefox Configuration Editor (about:config page). Support is not available for any changes made with the Configuration Editor so please do this at your own risk. Signing will be mandatory with no override, in Firefox 46 beta and release versions. For details, see this Mozilla blog. "

To do so, follow the below steps:

  • Open firefox and go to about:config
  • search for xpinstall.signatures.required
  • Double click it to set the option to false
  • Restart your browser