I USED to be able to see my email in 3rd party email apps. What happened Yahoo? Time to use GMail!

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Dave Byers commented
I had the MAIL app on my Windows PC and used to conglomerate other Mail apps to see all of my emails including Yahoo. About 3 months ago, the MAIL app stopped seeing new Yahoo emails. I switched to BlueMail and that had worked up until yesterday. I have also noted that my mail app on my Samsung can see Exhange Emails and Gmail, but now I can't see my Yahoo mails there either. What has happened to Yahoo mail and why is it blocking 3rd party Mail tools to see my emails?