I am using DomPDF, and some of the special characters are printed as a question-mark ("?").
An example was the checkmark ( β ).
After some research, an article on stackoverflow showed the answer:
http://stackoverflow.com/questions/5136067/dompdf-special-characters
The main problem is the default font.
At the moment, the default CSS file in entity-print only sets a single font:
font-family: sans-serif;
Instead, it needs to have something like this; this below worked for me, but other font-families are of course possible:
font-family: Verdana, Tahoma, "DejaVu Sans", sans-serif;
Then the characters showed up in the PDF.
It probably would be good to have something like this in the default CSS, or at least a comment in there that depending on the font/font-family that is used, you may not see some special-characters. However, since many people probably just try the default CSS, it should contain a working solution.
(Other note, I also changed the meta-tag in the template to this, but that seemed less of a problem)
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
...
</head>
) Not all content is available!
It's likely this issue predates Contrib.social: some issue and comment data are missing.
I tried so many ways to kill this problem.
I use wkhtmltopdf to product pdf with chinese characters(δΈζε符)
at last
...
This add to entity-print--webform-submission--notes.html.twig all is ok.
BUT IT'S IMPORTANT: if you use wkhtmltopdf,you must download font SimSun and set as first font like this
body {
font-family: "SimSun","Microsoft YaHei", Helvetica, Arial, sans-serif;
}