In an effort to protect users from too much spam, Gmail and Yahoo Mail have introduced some new guidelines that add some more checks and controls f...
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Great blog post.
There are lots of known real-time email validators available. They go beyond the rules which you have mentioned.
Never bounce is trusted by multiple bigger corporates like Dell, Uber, Indeed etc.
Here are some of the known vendors out there.
Suggestion
Thanks, Ranjan for the feedback. I've shared this internally with the team and will let you know once we address it.