Hello,
I’m having trouble of figuring out if it’s possible to change the scale for FF57 using the WebExtensions API. Spesifically I’m interested into changing the layout.css.devPixelsPerPx value.
Can this be done or is this not implemented anymore?
I searched a bit some days ago. I’d like to share what I learned.
WebExtension API blocks direct access for most user preferences. It is preferred that higher level API be implemented (reference in mozilla wiki).
But there are cases where preferences are exposed to web extensions with browserSettings permission. They are currently determined on a case-by-case basis, as stated in reference in bugzilla.
As currently there are no related entries listed on WebExtensions API docs, my understanding would be that it is not implemented.
But there are no related bugs in bugzilla, either. So perhaps you can try to get in touch, and ask if implementation is possible.