substack message: "Please enter a valid email; We were unable to validate your email domain"
https://cdn.fosstodon.org/media_attachments/files/113/475/502/073/012/698/original/6391b42eea55f53b.png
Substack is blocking https://kill-the-newsletter.com which turns a newsletter into an RSS feed.
What an incredibly asshole thing to do.
To get around you can setup an auto forward to the KTN bridge and subscribe with an email alias.
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