WebExtension Docs

Trigger: !webext

Try it

Kagi would openhttps://developer.mozilla.org/en-US/search?q=string+formatting&topic=addons

Run !webext in Kagi

URL pattern: https://developer.mozilla.org/en-US/search?q=query&topic=addons

Searches developer.mozilla.org, filed under Languages (javascript).

Other bangs for developer.mozilla.org