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Emails have this weird text on them

So the subject line has this weird chr at the end of the subject. Any ideas why
=?UTF-8?B?MjAyMj8=?=
IE here is the Discussion title
Royal Cup April 2022
but the email subject will says
Royal Cup April =?UTF-8?B?MjAyMj8=?=
0
Comments
What service are you using to send the emails?
I have my own Linux server and I'm just using sendMail to send it out
It looks like the encoding isn't making it to Sendmail correctly.
I don't know the solution, but this looks like the technical bits of where the hand-off is going awry: https://ncona.com/2011/06/using-utf-8-characters-on-an-e-mail-subject/