Firefox 41 disables ABP for being unsigned

[SilverbackNet]

Firefox 41 has just started demanding signed extensions and disables any that aren't, and ABP was one of the ones I lost few days ago. In 41, you can set xpinstall.signatures.required=false to get the old behavior back, but from 42 on it'll work in Developer and Nightly only. This is the link FF points me to.

FF 41 is in Developer channel now, about to be lifted to beta, so there's only six weeks or so until it starts to affect release users.

Edit: Never mind, I just redownloaded from mozilla.org and it worked. Dunno why trying to update when it was disabled didn't do anything. Since FF doesn't seem to consider a plain version vs a signed version an update, it might be worth re-releasing it with a version bump.

[Gingerbread Man]

Mozilla are the ones in charge of signing add-ons. If you find any unsigned add-ons on the Firefox Add-ons site, address your complaint to them by filing a new report in Bugzilla.
Previously, signed add-ons used to have version numbers like 2.6.9.1-signed but it seems this was done just for the initial signed versions. Presumably at this stage, updates are only supposed to be available once they're signed.

If you're using either Developer Edition or Nightly, you should use the latest development build of Adblock Plus. It's unsigned (from adblockplus.org, not the Firefox Add-ons site), so xpinstall.signatures.required must be set to false.