Igalia's model almost certainly couldn't cover maintenance of the entire browser engine and the desktop/mobile browsers, yet alone any ongoing improvement. It g

Igalia's model almost certainly couldn't cover maintenance of the entire browser engine and the desktop/mobile browsers, yet alone any ongoing improvement. It gets specific platform ports supported on an ongoing basis (typically for embedded platforms) and new features of interest to their paying customers supported (which are, inevitably, mostly major corporations), but that's largely it. As far as I'm aware, Firefox is the browser engine they contribute least to: they have many more clients who have much more interest in WebKit or Chromium based browsers and that's where the majority of work goes.