Font not displaying properly, apparently due to JavaScript error

I am using Anki 2.1.22 manually installed on Ubuntu 20.04.2. I’ve installed a font called _YUMIN.ttf both systemwide and in Anki’s media folder, but when I view a card that is supposed to show the font, it instead displays the text in a bold gothic type, and the following javascript error prints to /dev/stderr:

JS error on line 0: Access to font at ‘http://127.0.0.1:44135/_YUMIN.ttf’ from origin ‘null’ has been blocked by CORS policy: No ‘Access-Control-Allow-Origin’ header is present on the requested resource.

I’m finding ways online to fix that javascript error, but I don’t where the error is happening. Anki doesn’t include any javascript as far as I know. Does anyone know what might be wrong? I’ve installed three other CJK fonts for use in Anki, and none of them have this problem.

Please try the steps on When problems occur - Frequently Asked Questions