diff --git a/pkgs/development/tools/slimerjs/default.nix b/pkgs/development/tools/slimerjs/default.nix
index fd3f48b8b82..67a70b42bc4 100644
--- a/pkgs/development/tools/slimerjs/default.nix
+++ b/pkgs/development/tools/slimerjs/default.nix
@@ -34,7 +34,7 @@ stdenv.mkDerivation {
     echo 'export SLIMERJSLAUNCHER=${firefox}/bin/firefox' >>  "$out/bin/slimerjs"
     echo "'$out/lib/slimerjs/slimerjs' \"\$@\"" >> "$out/bin/slimerjs"
     chmod a+x "$out/bin/slimerjs"
-    sed -e 's@MaxVersion=32[.]@MaxVersion=33.@' -i "$out/lib/slimerjs/application.ini"
+    sed -e 's@MaxVersion=3[0-9][.]@MaxVersion=40.@' -i "$out/lib/slimerjs/application.ini"
   '';
   meta = {
     inherit (s) version;