Importing through GUI was possible before, but due to a regression one has to do it manually now.

Copy the .tox profile to ~/.config/tox/

Copy the .tox profile to %APPDATA\tox\

Go to your profile page (click on an avatar) and click on Export. Save your .tox profile somewhere.

µTox doesn't support importing / exporting profiles from within application, which forces users to manually move files around.

Copy the .tox profile to ~/.config/tox/ and name it tox_save.tox.

Copy the .tox profile to %APPDATA\roaming\tox\ and name it tox_save.tox.

Copy the tox_save.tox file from ~/.config/tox/.

Copy the tox.save.tox file from %APPDATA\roaming\tox\.