Chinese characters will be replaced by # when exporting a page to PDF

I'm using the xwiki v9.1.2 and I found that when exporting a page to PDF, the non-English characters will be replaced by "#".

I spent a lot of time searching in jira.xwiki.org and found that there's similar issues like XWIKI-4724 and XWIKI-1609. However, non of the solutions work on me.

Finally I found this commit log in github - https://github.com/xwiki/xwiki-platform/commit/437f28bee5545670b2478c93498f2f261a021aa5 and I manually create a fop-config.xml file in xwiki\WEB-INF\classes folder, with the "<auto-detect/>" not commented out. Then the problem solved.