As others have said, the goal ultimately with this kind of work is (or should be) standardization. Web tech-based apps really should be able to run anywhere you have a decent browser.
(I work for Mozilla, but not on our Apps work specifically)
Yeah, there's been discussions between the teams working on this at Google and Mozilla. I think the lack of coordination on a standard at this point is mostly because everything is still very much evolving. No one's sure exactly what's right, and we all learned the dangers of premature/aspirational standards from the start of the last decade (e.g. SVG). This is the time to iterate and figure out what works. The standards time will come once there's some real-world experience in what they should be.
There are various reasons why no one has chosen to implement that standard. My personal discomfort is that it basically punts on the security portion and leaves most of the scary stuff entirely at the discretion of the implementor. For that reason alone I personally think the spec is a non-starter.
https://www.mozilla.org/en-US/apps/partners/
As others have said, the goal ultimately with this kind of work is (or should be) standardization. Web tech-based apps really should be able to run anywhere you have a decent browser.
(I work for Mozilla, but not on our Apps work specifically)