QUOTE(Decrepit @ Oct 31 2017, 02:07 PM)

What the...?????? Turned on the computer this morning. Launched Firefox. Navigated to YouTube. Ads!!!!!! My ad blocker of choice (Adblocker Ultimate), while enabled, no longer functions.
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ADDENDUM: I disabled Adblocker Ultimate and enabled my old standby, Ad Block Plus. ABP still works. Thing is, it is labeled "LEGACY" so will cease to function with the release of Firefox v5.7 in two weeks.
A similar thing has been happening to me with Firefox/NoScript (which I don't run to block ads per se, but I so seriously don't want their scripts running). It's always proved easy to re-enable it, though (going to NoScript site, clicking re-install, does it in an instant). And it too is marked down as LEGACY.
But this seems to have stopped in the past week. So I'd say this is more along the lines of FF v5.7 prelaunch glitches - for a start, NoScript is just too important a security add-on to be completely sabotaged. (Backing up my NoScript whitelist, tho, just in case the changeover is non-smooth...)