Maybe the setting has a bad name (not actually a default), but we use it in the way it is intented. Read: https://github.com/maccesch/cmsplugin-contact#default_from_email

We could rename it to something like ``CMSPLUGIN_CONTACT_FROM_EMAIL`` for clarity. Maybe open a separate issue for this?

At any rate, this should be a two-step process so that we don't break existing installations:
a. Support both old and new setting names and we throw a deprecation warning if the old one is used. Make a maintenance release so that everyone is informed of the upcoming change.
b. After 6-12 months support for the old setting is removed.

So, this has to be done preferrably by @maccesch :-)