Chat messages are encrypted when they are sent over the network and decrypted when received. For privacy and security, a decrypted message exists only in the chat window, and it disappears from memory when Underpass is quit. If you receive an image file in a message, you can view the image directly in the chat window. If you want to keep the image file, however, or if you receive a non-image file, you will need to save the file to your Mac.
There are two ways to save a file from a chat message:
Underpass will give the file a default name. If you wish, you can rename the file in Finder after you've dropped it.
This command will open a save panel, and then you can enter the name of the file and select the location to save it.
Next: Chat Notifications