diff --git a/pkgs/by-name/firefox-extensions/package.nix b/pkgs/by-name/firefox-extensions/package.nix
index 0232f08d6..452b95cd0 100644
--- a/pkgs/by-name/firefox-extensions/package.nix
+++ b/pkgs/by-name/firefox-extensions/package.nix
@@ -167,9 +167,12 @@ let
       ublock-origin = fetchVersionedAddon rec {
         extid = "uBlock0@raymondhill.net";
         pname = "ublock-origin";
-        # N.B.: a handful of versions are released unsigned
-        url = "https://github.com/gorhill/uBlock/releases/download/${version}/uBlock0_${version}.firefox.xpi";
-        # url = "https://github.com/gorhill/uBlock/releases/download/${version}/uBlock0_${version}.firefox.signed.xpi";
+        # N.B.: the release process seems to be to first release an unsigned .xpi,
+        #       then sign it a few days later,
+        #       and then REMOVE THE UNSIGNED RELEASE.
+        #       therefore, only grab signed releases, to avoid having the artifact disappear out from under us :(
+        # url = "https://github.com/gorhill/uBlock/releases/download/${version}/uBlock0_${version}.firefox.xpi";
+        url = "https://github.com/gorhill/uBlock/releases/download/${version}/uBlock0_${version}.firefox.signed.xpi";
         version = "1.63.0";
         hash = "sha256-RqleAoNzRCRTwH/MMSi0wuo+/G875yc3csyXNcqJO+Q=";
       };