I saw an article that touched on this for the pinephone (not the pro) and they said that it made and received calls fine but did not originally have dtmf suppor

I saw an article that touched on this for the pinephone (not the pro) and they said that it made and received calls fine but did not originally have dtmf support. If you need to check your voicemail and enter a passcode or use an automated system to pick up your prescription, you could not use it for that. It seems that has been ironed out depending on which OS you put on it.