Pipes | are being converted to HTML entity

[ChrisThompsonTLDR]

MailChimp merge tags use *| and |* to open and close the tags.

When an HTML email is run through the inliner, these come back as *%7CUNSUB%7C*

https://github.com/tijsverkoyen/CssToInlineStyles/blob/master/example/examples/sumo/index.htm#L6 has an example of MailChimp merge tags, but I highly doubt they actually work.