Consider supporting prefs with a `devtools.` prefix

[Jee-Hex]

The Preferences policy currently (140.0esr) does not support setting prefs with a devtools. prefix. For example, since bug 1686929 Inspect Accessibility Properties will only appear in the context menu when devtools.everOpened is true. It would also be nice if we would be able to clear devtools.netmonitor.customRequest and/or devtools.debugger.pending-selected-location, both of which can be remembering information that users may not otherwise expect the browser to.

[mkaply]

Would it not be simpler to just disable devtools?

I guess I'm not understanding the usecase where a non developer would encounter this.

[Jee-Hex]

Would it not be simpler to just disable devtools?

That would work for the latter two examples, but I am not sure how disabling devtools would help if I also wanted devtools.everOpened to be true by default.

[mkaply]

Ah, I see. You want the accessibility inspector to always be there. I thought you were saying the opposite, that you didn't want it to appear after devtools was opened. I'll open a bug for this.