The relevant information is presented in the comment section below the bug report proper. If you would like a particular post to be pointed towards, here is one reprinted and slightly edited for clarity:
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Dave Townsend [:mossop] Assignee
Comment 15 • 10 months ago
(In reply to Hexandcube from comment #12)
>I disagree, many people have been waiting for PWA support in Firefox. Removing this feature, may result in people (including me, a huge Firefox advocate) switching from Firefox, to a browser that supports PWA. I'm very disappointed.
We already don't have the feature working in any decent fashion so I'm not sure removing it will have any impact here.
>I also would like to see the results of the research, Dave was talking about.
Unfortunately I think that the research is confidential at the moment.
(In reply to joshas from comment #13)
>You should reconsider this decision. It is understandable that currently there might not be enough resources to finish full PWA support, like in competing browsers, but removing it completely will not only make all work done on it a waste of time, but also send wrong signal to some users.
>Leaving feature hidden under flag for enthusiasts to experiment on and, maybe, even submit patches that will nudge it closer to completion - that would be a bigger win, than removing feature altogether.
The signal I hope we are sending is that *PWA support is not coming to desktop Firefox anytime soon* {emphasis: mine}. At this point I don't think we would accept patches to improve the feature so I don't think leaving the code in Firefox makes any sort of sense. Speaking as the developer who spent a good deal of time writing most of the code I am frustrated to see it removed too, but it is the decision that makes sense at this time.
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