linphone-3.6.1-10.fc23.x86_64 only allows entering DTMF tones after clicking on the stylized keypad symbol (which is easy to miss), and then you have to click on the buttons for each digit.  Pressing digits on the keyboard to trigger DTMF tones does not work.

This is very cumbersome for things like conference dial-ins.

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Rawhide has linphone 3.6.1 as well, so I assume that it's not fixed there, either.

This package has changed maintainer in Fedora. Reassigning to the new maintainer of this component.