diff --git a/testing/xpcshell/mach_test_package_commands.py b/testing/xpcshell/mach_test_package_commands.py
index dd4c576a10f4..dca206794233 100644
--- a/testing/xpcshell/mach_test_package_commands.py
+++ b/testing/xpcshell/mach_test_package_commands.py
@@ -22,7 +22,6 @@ from mach.decorators import (
 def run_xpcshell(context, **kwargs):
     args = Namespace(**kwargs)
     args.appPath = args.appPath or os.path.dirname(context.firefox_bin)
-    args.e10s = context.mozharness_config.get('e10s', args.e10s)
     args.utility_path = context.bin_dir
     args.testingModulesDir = context.modules_dir