Font Ignored when Generating PNG of Chart

[Thimows]

Description

When generating a PNG of a chart, the font seems to be ignored. It seems to default to a (very ugly) system default font

Steps to Reproduce

1. Open this code pen: https://codepen.io/thimows/pen/vYMdjgN
2. Use the hamburger menu in the top right of the chart to generate a PNG
3. You will see that the font is different

Screenshots

How the chart looks in the browser:

How the PNG export looks:

Reproduction Link

https://codepen.io/thimows/pen/vYMdjgN