Can’t upload custom TTF font – “A problem occurred…”

Hi there

I’m trying to upload a custom font to use in my PDFs. I give it a name and drag the .ttf file successfully, but get “A problem occcurred. Reload the page and try again.” error message. The font I would like to add is “Great Vibes” from Google Fonts. I have successfully added “Roboto”, but Great Vibes is causing the issue.

The .ttf is uploaded, though. I can see it in the uploads/PDF_EXTENDED_TEMPLATES/fonts folder. It just isn’t being registered in the dashboard.