Issue Summary

When a user previews a MS Word ".docx" file which contains characters with "Meiryo" ("メイリオ" in Japanese) font, those characters are displayed as square boxes. The issue occurs with or without "confluence.document.conversion.words.defaultfontname" system property. Disabling the sandbox didn't resolve the issue.
If "MS Gothic" is specified instead of "Meiryo", the preview works as expected.

Steps to Reproduce

Prereq:

• Create a .docx file which contains Japanese characters "あいうえお" with a font "Meiryo"
  sample file: testdoc-meiryo.docx
• Create another .docx file which contains Japanese characters "あいうえお" with a font "MS Gothic" (for comparison)
  sample file: testdoc-msgothic.docx
• Install "IPAGothic" font on the host OS
  Ubuntu example: "sudo apt install fonts-ipafont"

Procedure without specifying system properties:

1. Create a page on your Confluence instance, then attach two .docx files
2. Publish the page
3. Preview attached files

Procedure with system properties:

1. Add those system properties in the "setenv.sh" file of Confluence

   CATALINA_OPTS="-Dconfluence.document.conversion.fontpath=/usr/share/fonts/ -Dconfluence.document.conversion.slides.defaultfontname.regular=IPAGothic -Dconfluence.document.conversion.slides.defaultfontname.asian=IPAGothic -Dconfluence.document.conversion.slides.defaultfontname.symbol=IPAGothic ${CATALINA_OPTS}"
   CATALINA_OPTS="-Dconfluence.document.conversion.words.defaultfontname=IPAGothic ${CATALINA_OPTS}"
   
   CATALINA_OPTS="-Dconversion.sandbox.java.options=-Dconfluence.document.conversion.fontpath=/usr/share/fonts/,-Dconfluence.document.conversion.slides.defaultfontname.regular=IPAGothic,-Dconfluence.document.conversion.slides.defaultfontname.asian=IPAGothic,-Dconfluence.document.conversion.slides.defaultfontname.symbol=IPAGothic,-Dconfluence.document.conversion.words.defaultfontname=IPAGothic  ${CATALINA_OPTS}"
   

1. Create a page on your Confluence instance, then attach two .docx files
2. Publish the page
3. Preview attached files

Expected Results

Both preview shows Japanese characters "あいうえお".

Actual Results

Characters specified as "Meiryo" font displayed as square boxes.

Characters with "MS Gothic" displayed correctly.

Workaround

Currently there is no known workaround for this behavior. A workaround will be added here when available.