Revert "optimism"

This reverts commit 951c7cd848a6adbbc6f6c67157e0e71b495166b1.

.circleci/config.yml

diff --git a/.circleci/config.yml b/.circleci/config.yml
index 8229906..81e7aa0 100644
--- a/.circleci/config.yml
+++ b/.circleci/config.yml
@@ -263,7 +263,8 @@
             CHROME_FLAGS_NOCACHE: "--disk-cache-dir=/dev/null --disk-cache-size=1 --media-cache-size=1 --disable-application-cache --incognito"
           command: |
             export EMTEST_BROWSER="/usr/bin/google-chrome $CHROME_FLAGS_BASE $CHROME_FLAGS_HEADLESS $CHROME_FLAGS_WASM $CHROME_FLAGS_NOCACHE"
-            python3 tests/runner.py browser
+            # skip test_zzz_zzz_4GB_fail as it OOMs on the current bot
+            python3 tests/runner.py browser skip:browser.test_zzz_zzz_4GB_fail
   test-upstream-sockets-chrome:
     description: "Runs emscripten sockets tests under chrome"
     steps: