Describe the bug

WordCamp tickets provides invoice features, but the characters input in form fields disappear in Invoice PDF

To reproduce

Steps to reproduce the behavior:

1. Buy ticket in WordCamp.
2. Click on 'I need an invoice'
3. Enter name and address in form fields with Japanese characters.
4. The PDF attached to email has no Japanese characters.

Expected behavior

• Japanese(and maybe non-western characters) will display.
• Or else, display instructions that indicates available characters.

In my opinion, this is because of fonts installed in OS of the web server(FPDF way) or client(Node & headless chrome way).
This is a typical "the abyss of internationalization", so latter approach is reasonable.
Installing bunch of fonts is not reasonable. Only single Japanese font file is more than 5MB, it may be bigger than all western fonts. There are also Chinese, Korean, and so on.

Screenshots / Screencasts

Attached above.

WordCamp

Maybe all WordCamp sites.

System (please complete the following information)

This doesn't depend on client side.

Security Issues

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