This wikiHow will teach you how to read a message from Snapchat without the other person receiving notifications.
Steps
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Step 1. Launch the Snapchat app
Tap the yellow icon with the white ghost.
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Step 2. Tap the "Chat" icon
It's the small message icon at the bottom left of the screen. Touching this icon opens the chat screen.
To open the chat screen, you can swipe your finger across the screen to the right
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Step 3. Press and hold your finger on the screen
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Step 4. Drag it to the right
This will highlight the conversation on your screen, allowing you to read without physically opening the conversation (which would notify the sender that the message has been read).
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Step 5. Read the message
However, you will not be able to scroll down or up.
Make sure you keep your finger pressed on the screen. If you release it, the conversation will open and the message will be marked as read
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Step 6. Drag your finger left again
This will take you back to the chat screen.
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Step 7. Take your finger off the screen
The message will remain "intact".