Like stories, disappearing DMs are messages that expire. However, disappearing DMs can just be photos or videos and if you take an Instagram DM screenshot of this kind of messages, YES! Instagram will notify the other user or group members that you have taken an Instagram DM screenshot.
But how can you send disappearing messages? As mentioned above, disappearing messages can just include photos and videos. To send a disappearing message, you must tap the camera bottom on the left side of the message box and simply take a photo or a video from whatever you want.
In a nutshell, when you are taking an Instagram DM screenshot, you have to be aware of the type of messages you have sent or received, i.e. whenever you want to take an Instagram DM screenshot if the message is a disappearing one, the other side will be notified by Instagram. But if you’re going to take a screenshot from the whole chat screen in a private or a group, there is no need to worry.