diff --git a/scripts/travisci-test-extensions b/scripts/travisci-test-extensions
index 38fc6ce..9c1bdbd 100755
--- a/scripts/travisci-test-extensions
+++ b/scripts/travisci-test-extensions
@@ -17,6 +17,7 @@ fi
 
 . "${TRAVIS_BUILD_DIR}/scripts/common"
 
+ALREADY_TESTED_EXTENSIONS=''
 
 # Get the docker image ID for a PHP extension and a PHP version
 #
@@ -95,12 +96,13 @@ testNewExtensionLine () {
 	if test $# -lt 2; then
 		printf 'Missing PHP version list for the new extension %s\n' "${1:-}"
 		testNewExtensionLine_rc=1
-	else
+	elif ! stringInList "$1" "$ALREADY_TESTED_EXTENSIONS"; then
 		printf '### TESTING NEW EXTENSION %s ###\n' "${1}"
 		if test -n "$(printf '%s' "${1}" | sed -E 's/^[a-z][a-z0-9\-\_\.]+$//')"; then
 			printf '   INVALID PHP EXTENSION NAME: %s\n' "${1}" >&2
 			testNewExtensionLine_rc=1
 		else
+			ALREADY_TESTED_EXTENSIONS="$ALREADY_TESTED_EXTENSIONS $1"
 			testNewExtensionLine_extension="${1}"
 			while test $# -ge 2; do
 				shift
@@ -203,12 +205,15 @@ testExtensionsFromMessage () {
 		fi
 		IFS=' '
 		for TEST_EXTENSION in $TEST_EXTENSIONS; do
-			printf '### TESTING EXTENSION %s ###\n' "$TEST_EXTENSION"
-			for TEST_PHPVERSION in $(getAllPHPVersionsFor $TEST_EXTENSION); do
-				if ! testExtension "$TEST_EXTENSION" "$TEST_PHPVERSION"; then
-					testExtensionsFromMessage_result=1
-				fi
-			done
+			if ! stringInList "$TEST_EXTENSION" "$ALREADY_TESTED_EXTENSIONS"; then
+				ALREADY_TESTED_EXTENSIONS="$ALREADY_TESTED_EXTENSIONS $TEST_EXTENSION"
+				printf '### TESTING EXTENSION %s ###\n' "$TEST_EXTENSION"
+				for TEST_PHPVERSION in $(getAllPHPVersionsFor $TEST_EXTENSION); do
+					if ! testExtension "$TEST_EXTENSION" "$TEST_PHPVERSION"; then
+						testExtensionsFromMessage_result=1
+					fi
+				done
+			fi
 		done
 	done
 	resetIFS