In the current release of jTox (v1.3.0) using toxcore v.0.2.2, pressing the enter key will send the contents of your message input window instead of creating a new line. For multiple paragraphs, this can be worked around by copying and pasting a newline character into the tex tarea window, however I believe the best approach for jTox should be to configure the Enter key as new line and have a dedicated send button. Alternatively, holding Enter could create a new line while tapping enter could send the current message, this would save on screen real estate.
In the current release of jTox (v1.3.0) using toxcore v.0.2.2, pressing the enter key will send the contents of your message input window instead of creating a new line. For multiple paragraphs, this can be worked around by copying and pasting a newline character into the tex tarea window, however I believe the best approach for jTox should be to configure the Enter key as new line and have a dedicated send button. Alternatively, holding Enter could create a new line while tapping enter could send the current message, this would save on screen real estate.