diff --git a/pkgs/applications/networking/browsers/firefox/packages/firefox-beta.nix b/pkgs/applications/networking/browsers/firefox/packages/firefox-beta.nix
index b71647b7dd19..107d7d4fc95f 100644
--- a/pkgs/applications/networking/browsers/firefox/packages/firefox-beta.nix
+++ b/pkgs/applications/networking/browsers/firefox/packages/firefox-beta.nix
@@ -10,11 +10,11 @@
 buildMozillaMach rec {
   pname = "firefox-beta";
   binaryName = pname;
-  version = "143.0b8";
+  version = "143.0b9";
   applicationName = "Firefox Beta";
   src = fetchurl {
     url = "mirror://mozilla/firefox/releases/${version}/source/firefox-${version}.source.tar.xz";
-    sha512 = "bf8e78abcc1cf6c8b48a591d0185c85195a818de0d13bafa3f004ad9c76364a2c07cacdf09fe0ae2e290d9cbce7b8c3ba4b57793cd3d39240023ef53eea08377";
+    sha512 = "b014e343ddba2e3750a0f50925c9b7f07237593c299604d96275f45332063f1487a47234411f7c952ee50ffaeb385a22dedbc4f924e4e0fc89668172b06c78fd";
   };
 
   meta = {