@Tangy: You appear to have this setting checked (Prevent WebRTC from leaking local IP addresses) while using New Moon; in all honesty, I don't think it has any bearing on New (Pale) Moon, since WebRTC is disabled there at code level... But it's certainly applicable on FirefoxESR 52.9.0, Serpent 52.9.0 and even Serpent 55.0.0; the wiki link for that feature, for anyone concerned, is:
https://github.com/gorhill/uBlock/wiki/Prevent-WebRTC-from-leaking-local-IP-address
According to tests I performed on both FirefoxESR 52.9.0 and Serpent 52.9.0, this issue you report appears to manifest itself exclusively with the WebExtension version of UBlock Origin ; if one installs the XUL version of uB0, currently at version 1.16.4.7, then the checkbox remains "clickable" no matter the value of boolean pref "media.peerconnection.enabled"; switch to the WE version of uBO (stable channel currently at version 1.17.4) and one discovers that the WebRTC checkbox has been disabled (and text greyed out ), again irrespective of the state of the "media.peerconnection.enabled" boolean pref...
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A word to those using uB0 WE on Basilisk/Serpent 52.9.0 :
1.17.4 is the final version that can be installed in Basilisk 52 out of the box; 1.17.7b2 of the dev channel was (has now been removed from the GitHub repo) equally the last (beta) version to install (out-of-the-box) in either Basilisk 52 / Serpent 52.9.0; this development has been reported first in the official PM forums,
https://forum.palemoon.org/viewtopic.php?f=61&t=21241
which also links to the uB0 support reddit:
Mozilla fanbois aside (they're so irritating , aren't they?), it was claimed that "Basilisk was never officially supported", while in the end of the thread the author revealed that he had to increase "strict_min_version" (inside extension's manifest.json) to "55.0", because he started using the Web API requestIdleCallback. So, latest dev version 1.17.7rc2 won't install in Bk52
I've done some research and have discovered at least two discrepancies here:
1. For some inexplicable reason, Firefox versions 52.0.2 and 53.0.3 (release channel) as well as 52.9.0 (ESR channel) do not honour the "strict_min_version": "55.0" requirement and version uB0 1.17.7rc2 has no problem installing and working there...
2. While the MDN documentation states that window.requestIdleCallback() is "Implemented but disabled by default" in Firefox v53-55, I found boolean pref "dom.requestIdleCallback.enabled" extant (but defaulted to false) in all 3 mentioned Firefox versions (52.0.2, 52.9.0, 53.0.3); so, at least in theory, Firefox >=52.0 already meets the new requirement by @gorhill, provided the user manually flips "dom.requestIdleCallback.enabled" to true; what is even more important is the fact Moonchild devs have already defaulted that pref to true in Basilisk 52, so there's no actual reason why the Basilisk browser should be exempt from the list of supported (by latest uB0 WE) browsers - but, sadly, @gorhill does not follow closely Basilisk's development, hence his decision to block it based solely on its reported appVersion string ; also worth noting is that Serpent 55.0.0/moebius doesn't exhibit this issue because, its appVersion string reporting 55.*, it already fulfils the new enhanced requirements...
To cut a long story short, I downloaded file uBlock0_1.17.7rc2.firefox.signed.xpi to disk and manually changed line 5 in manifest.json file to read:
"strict_min_version": "52.0",
... then the extension had no problem installing and working as expected in Serpent 52.9.0
Of course, when Moonchild's new unfortunate plan (to remove WE support in Bk) bears fruits, this post of mine would be a moot one...
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