It actually is possible to add custom search engines, they are just hidden from users. If you create bool variable browser.urlbar.update2.engineAliasRefresh and set it to True in about:config you will enable the "Add" button under about:preferences#search window.
It's also a question, why is it disabled by default, and why is it under such obscure variable?
Anteriormente se podía realizar búsquedas en Yahoo y otros, pero actualmente no es posible, simplemente no hay opción, pues no aparece entre las opciones elegibles y tampoco permite agregarla.
Sería bueno agreguen opciones personalizables para que así el usuario pueda modificarlas a su elección.
Allow adding search engines manually
Previously you could search on Yahoo and others, but currently it is not possible, there is simply no option, since it does not appear among the eligible options and does not allow adding it either.
add support for manually adding search engine in firefox desktop
Hi,
I would like to be able to add search engine manually in Firefox desktop. This is for search engines like Google Scholar, on which the "add search engine" button don't show up.
This feature is already available in Firefox for android, and I don't see why it is not implemented for desktop Firefox too.