Xiaomi
Show or Hide Lock Screen Notification Content auf Xiaomi
MIUI lets you choose how much detail notifications reveal while your phone is locked. This is separate from per-app notification settings and applies to the lock screen display as a whole.
Three formats are usually available: showing the full notification content, showing that a notification arrived while hiding its text, or not displaying notifications on the lock screen at all. The first option is convenient for quickly checking messages, but it exposes senders and text to anyone near the device. The second option confirms activity without leaking details, which is useful in public or shared spaces. The third option keeps the lock screen clean but means you have to unlock the phone to see anything.
To change the format, go to Tap on Settings ➔ Tap on Notifications & Control center ➔ Tap on Lock screen ➔ Tap on Format ➔ Choose an option.
This setting applies globally to all apps by default. If only specific apps should hide content while others show it in full, check whether that app has its own notification style setting, since MIUI applies the lock screen format on top of individual app permissions.