Custom font upload problem

Hello there, and thank you for your plugin!

I have an issue with custom font upload https://prntscr.com/uhlm6o.
I tried to upload it as zip, but nothing happens. And after upload, there are some errors in my console https://prntscr.com/uhln0w.

The font I want to upload is futura, and here how it looks after unpacking https://prntscr.com/uhlnrv.
Can the problem be that all font files are in otf extension?

Will be glad to hear any solution of this or advice. Thanks!