personal-addon
Personal addon to test some browser extension stuff easily.
To enable Open URLs From Clipboard also for file:/// URLs, add the following three entries in about:config [source]:
capability.policy.policynames = "localfilelinks"
capability.policy.localfilelinks.checkloaduri.enabled = "allAccess"
capability.policy.localfilelinks.sites = "moz-extension://INTERNAL_UUID_OF_THE_ADDON"
The Internal UUID can be found on about:debugging#/runtime/this-firefox.