Thanks a lot, to this very, very smart extension ! :o)

FAQ+REQUEST: A place/site/help-text with a example list of real search engines & parameters would't be fine.
PS: Some search codes & strings from my FF (Foto) https://abload.de/img/add-on-swift-selectio8pj02.jpg

UPDATE 2.Sept.2020 -> PATH FOR LOCAL (Offline) ICONS: (In Windows must be in this Format) file:///c:\blabla\my-efb.ico
(Works only for the Context-Menu-Icons, not in Pop-Up) MORE: https://github.com/CanisLupus/swift-selection-search/issues/135