diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 4ac4ece8efc34ea7202d45c1c4aafda85041a420..d26d08f837dd37e403e7a49177c877366ec4540d 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -69,4 +69,4 @@ test-firefox:
   script:
     - cd ${HOME}
     # specify host here else it confuses the linked postgres image
-    - MOZ_FORCE_DISABLE_E10S=1 PGHOST=postgres yarn test:all:firefox
+    - PGHOST=postgres yarn test:all:firefox