See comments in http://wiki.hudson-ci.org/display/HUDSON/HTML+Publisher+Plugin:

Question
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htmlpublisher will modify the page encoding attribute of my program-generated HTML file from utf-8 to iso-8859-1~
That is from <meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /> to <meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1" >
Hence, my reports are filled with a bunch of gibberish instead of Chinese characters~
I wonder if anyone knows the solution here?
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Answer:
In this directory on my machine :home/hudson/.hudson/plugins/htmlpublisher/WEB-INF/classes/htmlpublisher/HtmlPublisher
There is this header.html, which is the default header attached to my code-generated html files.
Modify the charset and xml:lang="en" of the header.html~ the problem will be solved.

Though they are dated back to 2011, they're still actual:
Jenkings overrides encoding of the report with ISO-8859-1.

Please,

• either make encoding configurable somewhere
• or don't set encoding at all
• or use, at least, utf-8 instead of ISO-8859-1

Thanks!