Before its time and abandoned in the nick of it. And no one cares about native GUI's anymore apparently.
This is not written by us btw :)
Electron enabled cross-platform localized applications where nothing else stayed within the budget, with developers you already had.
It isn't that no one cares about native GUI's, it is that it isn't commerical, except in rare circumstances (games, visualization software, giant applications built by 1000s of developers, probably).
Webdevs have tried for 20 years to recreate these interfaces from scratch in HTML with still highly questionable results, and of course no real integration, visual or otherwise, with the host OS.
For me, the biggest impediment for writing XUL, when I was into FF extension development, was the extremely lackluster documentation. Despite Mozilla's ambitions they never seemed to promote the app development part of their platform much. It also suffered from much the same problems as Electron does today with performance and bloated memory usage compared to native apps. Though I imagine if they stuck with it, with the much improved JS and rendering engines (and multicore CPUs and 16gb standard RAM) in-use today, it would have become just as good enough as Electron is considered.
Fact is, HTML/CSS/JS benefits hugely from it's own inertia, and the near instant answers to most any question on Google/Stackoverflow. Hard to compete when you are basically an internal Mozilla project.
I'm sure Mozilla, or someone, could package the current Firefox stack in a similar way to Electron as an alternative, but it would be largely the same thing and have similar issues compared to native. So why bother I guess.
How's wxWidgets doing? Does anyone still use that?