Some email recipients get messages with =0D or =3D characters

Question

I have a LAMP web application that emails users. Some users have complained that instead of seeing html email messages, they see weird sequences of characters such as =0D o

Answer 1

When you see something like =3D, what you're seeing is a single character in what's called "quoted-printable" encoding. "=3D" is, in fact, an equal sign. =0D is a Carriage Return (CR), =0A is a Line Feed (LF)

Taken from Not all 'plain-text' is created equal...

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