Xiaomi
Manage Updates for System Apps auf Xiaomi
System apps on Xiaomi phones do not always update through the regular app store flow. Instead, MIUI bundles their update behavior into a dedicated updater tool, separate from notifications for regular apps.
If you never see a prompt when a system app changes, the notification toggle for this tool is probably switched off. If updates suddenly consume mobile data you did not expect, the download source is likely set to allow cellular data instead of Wi-Fi only.
To adjust this, go to Tap on Settings ➔ Tap on System apps updater ➔ Tap on Settings ➔ Enable or disable Show update notifications ➔ Tap on Auto updates ➔ Choose an option.
Turning notifications off does not stop updates from installing, it only hides the message. If you disable auto updates entirely, system apps stay on their current version until you check for updates manually, which can leave you without recent fixes or security patches.
If a single app misbehaves after an update, this setting will not roll it back. In that case, clearing the app cache or checking for a dedicated fix for that app is the better move, not changing the global updater settings.