diff --git a/Build/Scripts/runTests.sh b/Build/Scripts/runTests.sh
index 5ab632764b78eec66f642518b71b3802e70b2db1..3d91eda1234d7d12b93b0b30301a823f0359e584 100755
--- a/Build/Scripts/runTests.sh
+++ b/Build/Scripts/runTests.sh
@@ -39,6 +39,7 @@ setUpDockerComposeDotEnv() {
         echo "DOCKER_SELENIUM_IMAGE=${DOCKER_SELENIUM_IMAGE}"
         echo "IS_CORE_CI=${IS_CORE_CI}"
         echo "PHPSTAN_CONFIG_FILE=${PHPSTAN_CONFIG_FILE}"
+        echo "IMAGE_PREFIX=${IMAGE_PREFIX}"
     } > .env
 }
 
@@ -342,11 +343,15 @@ THISCHUNK=0
 DOCKER_SELENIUM_IMAGE="selenium/standalone-chrome:4.0.0-20211102"
 IS_CORE_CI=0
 PHPSTAN_CONFIG_FILE="phpstan.local.neon"
+IMAGE_PREFIX="ghcr.io/typo3/"
 
 # ENV var "CI" is set by gitlab-ci. We use it here to distinct 'local' and 'CI' environment.
 if [ "$CI" == "true" ]; then
     IS_CORE_CI=1
     PHPSTAN_CONFIG_FILE="phpstan.ci.neon"
+
+    # Set to empty to use docker hub (default) again. CI only until image cache issue has been solved in infrastructure.
+    IMAGE_PREFIX="typo3/"
 fi
 
 # Detect arm64 and use a seleniarm image.
@@ -860,12 +865,12 @@ case ${TEST_SUITE} in
         docker volume ls -q -f driver=local -f dangling=true | awk '$0 ~ /^[0-9a-f]{64}$/ { print }' | xargs -I {} docker volume rm {}
         echo ""
         # pull typo3/core-testing-*:latest versions of those ones that exist locally
-        echo "> pull typo3/core-testing-*:latest versions of those ones that exist locally"
-        docker images typo3/core-testing-*:latest --format "{{.Repository}}:latest" | xargs -I {} docker pull {}
+        echo "> pull ${IMAGE_PREFIX}core-testing-*:latest versions of those ones that exist locally"
+        docker images ${IMAGE_PREFIX}core-testing-*:latest --format "{{.Repository}}:latest" | xargs -I {} docker pull {}
         echo ""
         # remove "dangling" typo3/core-testing-* images (those tagged as <none>)
-        echo "> remove \"dangling\" typo3/core-testing-* images (those tagged as <none>)"
-        docker images typo3/core-testing-* --filter "dangling=true" --format "{{.ID}}" | xargs -I {} docker rmi {}
+        echo "> remove \"dangling\" ${IMAGE_PREFIX}core-testing-* images (those tagged as <none>)"
+        docker images ${IMAGE_PREFIX}core-testing-* --filter "dangling=true" --format "{{.ID}}" | xargs -I {} docker rmi {}
         echo ""
         ;;
     *)
diff --git a/Build/testing-docker/local/docker-compose.yml b/Build/testing-docker/local/docker-compose.yml
index 1ea21209eb64fb08db3dfbd401aa36d39c5a74ef..fef1fea4f2d4439ba95c8bf61af206477f69a47f 100644
--- a/Build/testing-docker/local/docker-compose.yml
+++ b/Build/testing-docker/local/docker-compose.yml
@@ -28,7 +28,7 @@ services:
       - /var/lib/postgresql/data:rw,noexec,nosuid
 
   web:
-    image: typo3/core-testing-${DOCKER_PHP_IMAGE}:latest
+    image: ${IMAGE_PREFIX}core-testing-${DOCKER_PHP_IMAGE}:latest
     user: "${HOST_UID}"
     stop_grace_period: 1s
     volumes:
@@ -55,7 +55,7 @@ services:
     image: memcached:1.5-alpine
 
   acceptance_split:
-    image: typo3/core-testing-${DOCKER_PHP_IMAGE}:latest
+    image: ${IMAGE_PREFIX}core-testing-${DOCKER_PHP_IMAGE}:latest
     user: "${HOST_UID}"
     volumes:
       - ${CORE_ROOT}:${CORE_ROOT}
@@ -80,7 +80,7 @@ services:
         echo Database is up;
       "
   acceptance_application_mariadb:
-    image: typo3/core-testing-${DOCKER_PHP_IMAGE}:latest
+    image: ${IMAGE_PREFIX}core-testing-${DOCKER_PHP_IMAGE}:latest
     user: "${HOST_UID}"
     environment:
       typo3DatabaseName: func_test
@@ -134,7 +134,7 @@ services:
         echo Database is up;
       "
   acceptance_application_mysql:
-    image: typo3/core-testing-${DOCKER_PHP_IMAGE}:latest
+    image: ${IMAGE_PREFIX}core-testing-${DOCKER_PHP_IMAGE}:latest
     user: "${HOST_UID}"
     environment:
       typo3DatabaseName: func_test
@@ -188,7 +188,7 @@ services:
         echo Database is up;
       "
   acceptance_application_postgres:
-    image: typo3/core-testing-${DOCKER_PHP_IMAGE}:latest
+    image: ${IMAGE_PREFIX}core-testing-${DOCKER_PHP_IMAGE}:latest
     user: "${HOST_UID}"
     volumes:
       - ${CORE_ROOT}:${CORE_ROOT}
@@ -238,7 +238,7 @@ services:
       "
 
   acceptance_application_sqlite:
-    image: typo3/core-testing-${DOCKER_PHP_IMAGE}:latest
+    image: ${IMAGE_PREFIX}core-testing-${DOCKER_PHP_IMAGE}:latest
     user: "${HOST_UID}"
     volumes:
       - ${CORE_ROOT}:${CORE_ROOT}
@@ -291,7 +291,7 @@ services:
         echo Database is up;
       "
   acceptance_install_mysql:
-    image: typo3/core-testing-${DOCKER_PHP_IMAGE}:latest
+    image: ${IMAGE_PREFIX}core-testing-${DOCKER_PHP_IMAGE}:latest
     user: "${HOST_UID}"
     environment:
       typo3InstallMysqlDatabaseHost: mysql
@@ -338,7 +338,7 @@ services:
         echo Database is up;
       "
   acceptance_install_mariadb:
-    image: typo3/core-testing-${DOCKER_PHP_IMAGE}:latest
+    image: ${IMAGE_PREFIX}core-testing-${DOCKER_PHP_IMAGE}:latest
     user: "${HOST_UID}"
     environment:
       typo3InstallMysqlDatabaseHost: mariadb
@@ -385,7 +385,7 @@ services:
         echo Database is up;
       "
   acceptance_install_postgres:
-    image: typo3/core-testing-${DOCKER_PHP_IMAGE}:latest
+    image: ${IMAGE_PREFIX}core-testing-${DOCKER_PHP_IMAGE}:latest
     user: "${HOST_UID}"
     environment:
       typo3InstallPostgresqlDatabaseHost: postgres
@@ -424,7 +424,7 @@ services:
         sleep 1;
       "
   acceptance_install_sqlite:
-    image: typo3/core-testing-${DOCKER_PHP_IMAGE}:latest
+    image: ${IMAGE_PREFIX}core-testing-${DOCKER_PHP_IMAGE}:latest
     user: "${HOST_UID}"
     volumes:
       - ${CORE_ROOT}:${CORE_ROOT}
@@ -449,7 +449,7 @@ services:
       "
 
   build_css:
-    image: typo3/core-testing-nodejs16:latest
+    image: ${IMAGE_PREFIX}core-testing-nodejs16:latest
     user: "${HOST_UID}"
     volumes:
     - ${CORE_ROOT}:${CORE_ROOT}
@@ -467,7 +467,7 @@ services:
       "
 
   build_javascript:
-    image: typo3/core-testing-nodejs16:latest
+    image: ${IMAGE_PREFIX}core-testing-nodejs16:latest
     user: "${HOST_UID}"
     volumes:
     - ${CORE_ROOT}:${CORE_ROOT}
@@ -485,7 +485,7 @@ services:
       "
 
   cgl_git:
-    image: typo3/core-testing-${DOCKER_PHP_IMAGE}:latest
+    image: ${IMAGE_PREFIX}core-testing-${DOCKER_PHP_IMAGE}:latest
     user: "${HOST_UID}"
     volumes:
     - ${CORE_ROOT}:${CORE_ROOT}
@@ -499,7 +499,7 @@ services:
       "
 
   cgl_all:
-    image: typo3/core-testing-${DOCKER_PHP_IMAGE}:latest
+    image: ${IMAGE_PREFIX}core-testing-${DOCKER_PHP_IMAGE}:latest
     user: "${HOST_UID}"
     volumes:
     - ${CORE_ROOT}:${CORE_ROOT}
@@ -513,7 +513,7 @@ services:
       "
 
   cgl_header_git:
-    image: typo3/core-testing-${DOCKER_PHP_IMAGE}:latest
+    image: ${IMAGE_PREFIX}core-testing-${DOCKER_PHP_IMAGE}:latest
     user: "${HOST_UID}"
     volumes:
       - ${CORE_ROOT}:${CORE_ROOT}
@@ -527,7 +527,7 @@ services:
       "
 
   cgl_header_all:
-    image: typo3/core-testing-${DOCKER_PHP_IMAGE}:latest
+    image: ${IMAGE_PREFIX}core-testing-${DOCKER_PHP_IMAGE}:latest
     user: "${HOST_UID}"
     volumes:
       - ${CORE_ROOT}:${CORE_ROOT}
@@ -542,7 +542,7 @@ services:
       "
 
   check_annotations:
-    image: typo3/core-testing-${DOCKER_PHP_IMAGE}:latest
+    image: ${IMAGE_PREFIX}core-testing-${DOCKER_PHP_IMAGE}:latest
     user: "${HOST_UID}"
     volumes:
     - ${CORE_ROOT}:${CORE_ROOT}
@@ -556,7 +556,7 @@ services:
       "
 
   check_test_class_final:
-    image: typo3/core-testing-${DOCKER_PHP_IMAGE}:latest
+    image: ${IMAGE_PREFIX}core-testing-${DOCKER_PHP_IMAGE}:latest
     user: "${HOST_UID}"
     volumes:
       - ${CORE_ROOT}:${CORE_ROOT}
@@ -570,7 +570,7 @@ services:
       "
 
   check_test_methods_prefix:
-    image: typo3/core-testing-${DOCKER_PHP_IMAGE}:latest
+    image: ${IMAGE_PREFIX}core-testing-${DOCKER_PHP_IMAGE}:latest
     user: "${HOST_UID}"
     volumes:
       - ${CORE_ROOT}:${CORE_ROOT}
@@ -584,7 +584,7 @@ services:
       "
 
   check_bom:
-    image: typo3/core-testing-${DOCKER_PHP_IMAGE}:latest
+    image: ${IMAGE_PREFIX}core-testing-${DOCKER_PHP_IMAGE}:latest
     user: "${HOST_UID}"
     volumes:
     - ${CORE_ROOT}:${CORE_ROOT}
@@ -598,7 +598,7 @@ services:
       "
 
   check_composer:
-    image: typo3/core-testing-${DOCKER_PHP_IMAGE}:latest
+    image: ${IMAGE_PREFIX}core-testing-${DOCKER_PHP_IMAGE}:latest
     user: "${HOST_UID}"
     volumes:
     - ${CORE_ROOT}:${CORE_ROOT}
@@ -612,7 +612,7 @@ services:
       "
 
   check_exception_codes:
-    image: typo3/core-testing-${DOCKER_PHP_IMAGE}:latest
+    image: ${IMAGE_PREFIX}core-testing-${DOCKER_PHP_IMAGE}:latest
     user: "${HOST_UID}"
     volumes:
     - ${CORE_ROOT}:${CORE_ROOT}
@@ -626,7 +626,7 @@ services:
       "
 
   check_extension_scanner_rst:
-    image: typo3/core-testing-${DOCKER_PHP_IMAGE}:latest
+    image: ${IMAGE_PREFIX}core-testing-${DOCKER_PHP_IMAGE}:latest
     user: "${HOST_UID}"
     volumes:
     - ${CORE_ROOT}:${CORE_ROOT}
@@ -640,7 +640,7 @@ services:
       "
 
   check_file_path_length:
-    image: typo3/core-testing-${DOCKER_PHP_IMAGE}:latest
+    image: ${IMAGE_PREFIX}core-testing-${DOCKER_PHP_IMAGE}:latest
     user: "${HOST_UID}"
     volumes:
     - ${CORE_ROOT}:${CORE_ROOT}
@@ -654,7 +654,7 @@ services:
       "
 
   check_git_submodule:
-    image: typo3/core-testing-${DOCKER_PHP_IMAGE}:latest
+    image: ${IMAGE_PREFIX}core-testing-${DOCKER_PHP_IMAGE}:latest
     user: "${HOST_UID}"
     volumes:
     - ${CORE_ROOT}:${CORE_ROOT}
@@ -671,7 +671,7 @@ services:
       "
 
   check_grunt_clean:
-    image: typo3/core-testing-nodejs16:latest
+    image: ${IMAGE_PREFIX}core-testing-nodejs16:latest
     user: "${HOST_UID}"
     volumes:
       - ${CORE_ROOT}:${CORE_ROOT}
@@ -693,7 +693,7 @@ services:
       "
 
   check_namespace_integrity:
-    image: typo3/core-testing-${DOCKER_PHP_IMAGE}:latest
+    image: ${IMAGE_PREFIX}core-testing-${DOCKER_PHP_IMAGE}:latest
     user: "${HOST_UID}"
     volumes:
       - ${CORE_ROOT}:${CORE_ROOT}
@@ -707,7 +707,7 @@ services:
       "
 
   check_permissions:
-    image: typo3/core-testing-${DOCKER_PHP_IMAGE}:latest
+    image: ${IMAGE_PREFIX}core-testing-${DOCKER_PHP_IMAGE}:latest
     user: "${HOST_UID}"
     volumes:
     - ${CORE_ROOT}:${CORE_ROOT}
@@ -721,7 +721,7 @@ services:
       "
 
   check_rst:
-    image: typo3/core-testing-${DOCKER_PHP_IMAGE}:latest
+    image: ${IMAGE_PREFIX}core-testing-${DOCKER_PHP_IMAGE}:latest
     user: "${HOST_UID}"
     volumes:
     - ${CORE_ROOT}:${CORE_ROOT}
@@ -735,7 +735,7 @@ services:
       "
 
   composer_install:
-    image: typo3/core-testing-${DOCKER_PHP_IMAGE}:latest
+    image: ${IMAGE_PREFIX}core-testing-${DOCKER_PHP_IMAGE}:latest
     user: "${HOST_UID}"
     volumes:
     - ${CORE_ROOT}:${CORE_ROOT}
@@ -751,7 +751,7 @@ services:
       "
 
   composer_install_max:
-    image: typo3/core-testing-${DOCKER_PHP_IMAGE}:latest
+    image: ${IMAGE_PREFIX}core-testing-${DOCKER_PHP_IMAGE}:latest
     user: "${HOST_UID}"
     volumes:
       - ${CORE_ROOT}:${CORE_ROOT}
@@ -769,7 +769,7 @@ services:
       "
 
   composer_install_min:
-    image: typo3/core-testing-${DOCKER_PHP_IMAGE}:latest
+    image: ${IMAGE_PREFIX}core-testing-${DOCKER_PHP_IMAGE}:latest
     user: "${HOST_UID}"
     volumes:
       - ${CORE_ROOT}:${CORE_ROOT}
@@ -787,7 +787,7 @@ services:
       "
 
   composer_test_distribution:
-    image: typo3/core-testing-${DOCKER_PHP_IMAGE}:latest
+    image: ${IMAGE_PREFIX}core-testing-${DOCKER_PHP_IMAGE}:latest
     user: "${HOST_UID}"
     volumes:
     - ${CORE_ROOT}:${CORE_ROOT}
@@ -806,7 +806,7 @@ services:
       "
 
   composer_validate:
-    image: typo3/core-testing-${DOCKER_PHP_IMAGE}:latest
+    image: ${IMAGE_PREFIX}core-testing-${DOCKER_PHP_IMAGE}:latest
     user: "${HOST_UID}"
     volumes:
     - ${CORE_ROOT}:${CORE_ROOT}
@@ -820,7 +820,7 @@ services:
       "
 
   functional_split:
-    image: typo3/core-testing-${DOCKER_PHP_IMAGE}:latest
+    image: ${IMAGE_PREFIX}core-testing-${DOCKER_PHP_IMAGE}:latest
     user: "${HOST_UID}"
     volumes:
       - ${CORE_ROOT}:${CORE_ROOT}
@@ -849,7 +849,7 @@ services:
         echo Database is up;
       "
   functional_mariadb:
-    image: typo3/core-testing-${DOCKER_PHP_IMAGE}:latest
+    image: ${IMAGE_PREFIX}core-testing-${DOCKER_PHP_IMAGE}:latest
     user: "${HOST_UID}"
     volumes:
       - ${CORE_ROOT}:${CORE_ROOT}
@@ -886,7 +886,7 @@ services:
         fi
       "
   functional_deprecated_mariadb:
-    image: typo3/core-testing-${DOCKER_PHP_IMAGE}:latest
+    image: ${IMAGE_PREFIX}core-testing-${DOCKER_PHP_IMAGE}:latest
     user: "${HOST_UID}"
     volumes:
       - ${CORE_ROOT}:${CORE_ROOT}
@@ -936,7 +936,7 @@ services:
         echo Database is up;
       "
   functional_mysql:
-    image: typo3/core-testing-${DOCKER_PHP_IMAGE}:latest
+    image: ${IMAGE_PREFIX}core-testing-${DOCKER_PHP_IMAGE}:latest
     user: "${HOST_UID}"
     volumes:
       - ${CORE_ROOT}:${CORE_ROOT}
@@ -973,7 +973,7 @@ services:
         fi
       "
   functional_deprecated_mysql:
-    image: typo3/core-testing-${DOCKER_PHP_IMAGE}:latest
+    image: ${IMAGE_PREFIX}core-testing-${DOCKER_PHP_IMAGE}:latest
     user: "${HOST_UID}"
     volumes:
       - ${CORE_ROOT}:${CORE_ROOT}
@@ -1023,7 +1023,7 @@ services:
         echo Database is up;
       "
   functional_postgres:
-    image: typo3/core-testing-${DOCKER_PHP_IMAGE}:latest
+    image: ${IMAGE_PREFIX}core-testing-${DOCKER_PHP_IMAGE}:latest
     user: "${HOST_UID}"
     volumes:
       - ${CORE_ROOT}:${CORE_ROOT}
@@ -1060,7 +1060,7 @@ services:
         fi
       "
   functional_deprecated_postgres:
-    image: typo3/core-testing-${DOCKER_PHP_IMAGE}:latest
+    image: ${IMAGE_PREFIX}core-testing-${DOCKER_PHP_IMAGE}:latest
     user: "${HOST_UID}"
     volumes:
       - ${CORE_ROOT}:${CORE_ROOT}
@@ -1102,7 +1102,7 @@ services:
         sleep 1;
       "
   functional_sqlite:
-    image: typo3/core-testing-${DOCKER_PHP_IMAGE}:latest
+    image: ${IMAGE_PREFIX}core-testing-${DOCKER_PHP_IMAGE}:latest
     user: "${HOST_UID}"
     tmpfs:
       - ${CORE_ROOT}/typo3temp/var/tests/functional-sqlite-dbs/:rw,noexec,nosuid,uid=${HOST_UID}
@@ -1137,7 +1137,7 @@ services:
         fi
       "
   functional_deprecated_sqlite:
-    image: typo3/core-testing-${DOCKER_PHP_IMAGE}:latest
+    image: ${IMAGE_PREFIX}core-testing-${DOCKER_PHP_IMAGE}:latest
     user: "${HOST_UID}"
     tmpfs:
       - ${CORE_ROOT}/typo3temp/var/tests/functional-sqlite-dbs/:rw,noexec,nosuid,uid=${HOST_UID}
@@ -1168,7 +1168,7 @@ services:
       "
 
   lint_php:
-    image: typo3/core-testing-${DOCKER_PHP_IMAGE}:latest
+    image: ${IMAGE_PREFIX}core-testing-${DOCKER_PHP_IMAGE}:latest
     user: "${HOST_UID}"
     volumes:
     - ${CORE_ROOT}:${CORE_ROOT}
@@ -1183,7 +1183,7 @@ services:
       "
 
   lint_scss:
-    image: typo3/core-testing-nodejs16:latest
+    image: ${IMAGE_PREFIX}core-testing-nodejs16:latest
     user: "${HOST_UID}"
     volumes:
     - ${CORE_ROOT}:${CORE_ROOT}
@@ -1201,7 +1201,7 @@ services:
       "
 
   lint_html:
-    image: typo3/core-testing-nodejs16:latest
+    image: ${IMAGE_PREFIX}core-testing-nodejs16:latest
     user: "${HOST_UID}"
     volumes:
     - ${CORE_ROOT}:${CORE_ROOT}
@@ -1219,7 +1219,7 @@ services:
       "
 
   lint_typescript:
-    image: typo3/core-testing-nodejs16:latest
+    image: ${IMAGE_PREFIX}core-testing-nodejs16:latest
     user: "${HOST_UID}"
     volumes:
     - ${CORE_ROOT}:${CORE_ROOT}
@@ -1237,7 +1237,7 @@ services:
       "
 
   list_exception_codes:
-    image: typo3/core-testing-${DOCKER_PHP_IMAGE}:latest
+    image: ${IMAGE_PREFIX}core-testing-${DOCKER_PHP_IMAGE}:latest
     user: "${HOST_UID}"
     volumes:
       - ${CORE_ROOT}:${CORE_ROOT}
@@ -1251,7 +1251,7 @@ services:
       "
 
   phpstan:
-    image: typo3/core-testing-${DOCKER_PHP_IMAGE}:latest
+    image: ${IMAGE_PREFIX}core-testing-${DOCKER_PHP_IMAGE}:latest
     user: "${HOST_UID}"
     volumes:
       - ${CORE_ROOT}:${CORE_ROOT}
@@ -1267,7 +1267,7 @@ services:
       "
 
   phpstan_generate_baseline:
-    image: typo3/core-testing-${DOCKER_PHP_IMAGE}:latest
+    image: ${IMAGE_PREFIX}core-testing-${DOCKER_PHP_IMAGE}:latest
     user: "${HOST_UID}"
     volumes:
       - ${CORE_ROOT}:${CORE_ROOT}
@@ -1283,7 +1283,7 @@ services:
       "
 
   unit:
-    image: typo3/core-testing-${DOCKER_PHP_IMAGE}:latest
+    image: ${IMAGE_PREFIX}core-testing-${DOCKER_PHP_IMAGE}:latest
     user: "${HOST_UID}"
     volumes:
       - ${CORE_ROOT}:${CORE_ROOT}
@@ -1308,7 +1308,7 @@ services:
       "
 
   unitDeprecated:
-    image: typo3/core-testing-${DOCKER_PHP_IMAGE}:latest
+    image: ${IMAGE_PREFIX}core-testing-${DOCKER_PHP_IMAGE}:latest
     user: "${HOST_UID}"
     volumes:
       - ${CORE_ROOT}:${CORE_ROOT}
@@ -1333,7 +1333,7 @@ services:
       "
 
   unitJavascript:
-    image: typo3/core-testing-nodejs16-chrome:latest
+    image: ${IMAGE_PREFIX}core-testing-nodejs16-chrome:latest
     user: "${HOST_UID}"
     volumes:
       - ${CORE_ROOT}:${CORE_ROOT}
@@ -1352,7 +1352,7 @@ services:
       "
 
   unitRandom:
-    image: typo3/core-testing-${DOCKER_PHP_IMAGE}:latest
+    image: ${IMAGE_PREFIX}core-testing-${DOCKER_PHP_IMAGE}:latest
     user: "${HOST_UID}"
     volumes:
       - ${CORE_ROOT}:${CORE_ROOT}