diff --git a/.gitea/workflows/release.yml b/.gitea/workflows/release.yml
index 972fd64..f8e555c 100644
--- a/.gitea/workflows/release.yml
+++ b/.gitea/workflows/release.yml
@@ -37,22 +37,25 @@ jobs:
           short_sha="$(printf '%s' "$GITEA_SHA" | cut -c1-7)"
           repo_owner="${GITEA_REPOSITORY%%/*}"
           registry_host="${GITEA_REGISTRY}"
+          app_name="$(printf '%s' "$APP_NAME" | tr '[:upper:]' '[:lower:]')"
 
           if [ -z "$registry_host" ]; then
             registry_host="$(printf '%s' "$GITEA_SERVER_URL" | sed -E 's#^https?://##; s#/$##')"
           fi
+          registry_host="$(printf '%s' "$registry_host" | tr '[:upper:]' '[:lower:]')"
 
           package_namespace="${GITEA_PACKAGE_NAMESPACE}"
           if [ -z "$package_namespace" ]; then
             package_namespace="${repo_owner}"
           fi
+          package_namespace="$(printf '%s' "$package_namespace" | tr '[:upper:]' '[:lower:]')"
 
           registry_username="${GITEA_REGISTRY_USERNAME}"
           if [ -z "$registry_username" ]; then
             registry_username="${GITEA_ACTOR}"
           fi
 
-          image_ref="${registry_host}/${package_namespace}/${APP_NAME}"
+          image_ref="${registry_host}/${package_namespace}/${app_name}"
 
           echo "SHORT_SHA=${short_sha}" >> "$GITHUB_ENV"
           echo "RELEASE_TAG=release-${short_sha}" >> "$GITHUB_ENV"