Fonts should not be referenced directly like that, relying on system level fonts. The proper way to use fonts in Perspective is to embed them as resources - look at <gateway directory>/data/modules/com.inductiveautomation.perspective/ - there is a fonts/ directory, and a themes/ directory. If you install a properly packaged web font in the fonts/ directory, you can then reference it in a @font-face selector in a new theme.css file; something like this test I did:
@font-face {
font-family: Test;
src: url("/data/perspective/fonts/almendra-sc-v10-latin-regular.woff"); }
You should use a new, custom .CSS file, because the light and dark theme.css files can and will be overwritten on upgrade, as we make changes to the themes and add new components.
