diff --git a/setup/bootstrap.sh b/setup/bootstrap.sh
index cc4c060e..b700ee52 100644
--- a/setup/bootstrap.sh
+++ b/setup/bootstrap.sh
@@ -19,7 +19,7 @@ if [ -z "$TAG" ]; then
 	# want to display in status checks.
 	#
 	# Allow point-release versions of the major releases, e.g. 22.04.1 is OK.
-	UBUNTU_VERSION=$( lsb_release -d | sed 's/.*:\s*//' | sed 's/\([0-9]*\.[0-9]*\)\.[0-9]/\1/' )"
+	UBUNTU_VERSION=$( lsb_release -d | sed 's/.*:\s*//' | sed 's/\([0-9]*\.[0-9]*\)\.[0-9]/\1/' )
 	if [ "$UBUNTU_VERSION" == "Ubuntu 22.04 LTS" ]; then
 		# This machine is running Ubuntu 22.04, which is supported by
 		# Mail-in-a-Box versions 60 and later.