I'll add those add-on searches. The idea is that third-party search engines are good for certain verticals and in those cases we let you quickly get to them.

There are a few cases where the collection doesn't have its own engine, and so I've turned it into a site: query on DDG. But for ones that have an engine, I figure you want to go there or else you could just search 'x firefox addon' or 'x'.

Creative commons search is !cc :)
posted by yegg Staff7 years and 5 months ago Link