diff --git a/.travis.yml b/.travis.yml
index a3f0bbfe..9209a957 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -13,6 +13,8 @@ matrix:
       env: OPENPGP_NODE_JS='8' OPENPGPJSTEST='unit'
     - node_js: "10"
       env: OPENPGP_NODE_JS='10' OPENPGPJSTEST='unit'
+    - node_js: "9"
+      env: BROWSER='Firefox' VERSION='26' PLATFORM='macOS 10.13' OPENPGPJSTEST='saucelabs' COMPAT=1
     - node_js: "9"
       env: BROWSER='Firefox' VERSION='61' PLATFORM='macOS 10.13' OPENPGPJSTEST='saucelabs'
     - node_js: "9"