gmr
Option to normalize without mxrecords lookup
Hi, I love this library and the rules it brings, I faced some issues when running this in an offline setting though, and was wondering if we can add an option to avoid mxrecords lookup (happy to submit a PR if you are open to the idea). This can also work even if online but you don't care about 100% accuracy (i.e. taking the domain input at face value). Do you think we can add that?
How would you accomplish this for non-obvious domains?
For example, my personal domain is hosted at Google, but you wouldn't know that without a MX lookup.
I guess it could go into reduced functionality mode and only have obvious domains that work in this mode, but that would be a greatly diminished functionality.
