diff --git a/Containers/mastercontainer/start.sh b/Containers/mastercontainer/start.sh
index 8aade3ab..0c253859 100644
--- a/Containers/mastercontainer/start.sh
+++ b/Containers/mastercontainer/start.sh
@@ -194,9 +194,9 @@ It is set to '$NEXTCLOUD_TRUSTED_CACERTS_DIR '."
     fi
 fi
 if [ -n "$NEXTCLOUD_STARTUP_APPS" ]; then
-    if ! echo "$NEXTCLOUD_STARTUP_APPS" | grep -q "^[a-z _-]\+$"; then
+    if ! echo "$NEXTCLOUD_STARTUP_APPS" | grep -q "^[a-z0-9 _-]\+$"; then
         echo "You've set NEXTCLOUD_STARTUP_APPS but not to an allowed value.
-It needs to be a string. Allowed are small letters a-z, spaces, hyphens and '_'.
+It needs to be a string. Allowed are small letters a-z, 0-9, spaces, hyphens and '_'.
 It is set to '$NEXTCLOUD_STARTUP_APPS'."
         exit 1
     fi
diff --git a/readme.md b/readme.md
index 22cbdf0c..604cec22 100644
--- a/readme.md
+++ b/readme.md
@@ -516,7 +516,7 @@ You can run AIO also with docker rootless. How to do this is documented here: [d
 No. Since Podman is not 100% compatible with the Docker API, you cannot use Podman instead of Docker (since that would add yet another platform where the maintaner would need to test on). However you can use and follow the [manual-install documentation](./manual-install/) to get AIO's containers running with Podman or use Docker rootless, as described in the above section.
 
 ### How to change the Nextcloud apps that are installed on the first startup?
-You might want to adjust the Nextcloud apps that are installed upon the first startup of the Nextcloud container. You can do so by adding `-e NEXTCLOUD_STARTUP_APPS="deck twofactor_totp tasks calendar contacts"` to the docker run command of the mastercontainer and customize the value to your fitting. It must be a string with small letters a-z, spaces and hyphens or '_'. You can disable shipped and by default enabled apps by adding a hyphen in front of the appid. E.g. `-contactsinteraction`.
+You might want to adjust the Nextcloud apps that are installed upon the first startup of the Nextcloud container. You can do so by adding `-e NEXTCLOUD_STARTUP_APPS="deck twofactor_totp tasks calendar contacts"` to the docker run command of the mastercontainer and customize the value to your fitting. It must be a string with small letters a-z, 0-9, spaces and hyphens or '_'. You can disable shipped and by default enabled apps by adding a hyphen in front of the appid. E.g. `-contactsinteraction`.
 
 ### How to add OS packages permanently to the Nextcloud container?
 Some Nextcloud apps require additional external dependencies that must be bundled within Nextcloud container in order to work correctly. As we cannot put each and every dependency for all apps into the container - as this would make the project very fast unmaintainable - there is an official way how you can add additional dependencies into the Nextcloud container. However note that doing this is disrecommended since we do not test Nextcloud apps that require external dependencies.