Little known fact is that the SGI 5.6+ (certainly 6) settings controls was the first "electron app". It ran a mozilla process, with CSS1.x to style the control

Little known fact is that the SGI 5.6+ (certainly 6) settings controls was the first "electron app". It ran a mozilla process, with CSS1.x to style the controls like Motif. And the Javascript code interacted with the underlying XUL hacks in a manner not much different from WebOS palm used decades later.