“Consistent” UX is often one of the downsides of cross platform frameworks. Android and iOS have distinct UX details that users expect in their apps.
Mozilla, and by extension the Firefox crew, lost sight of their core competencies a long time ago. Every dumbass design decision the Chrome folks make, Mozilla will emulate a few years later.
However, what is this about separate search and url boxes? I have that, still. You don't have to have just the single box. Still, the main url box still behaves as a search either way. Is that what you mean?