UserAgent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_13_3) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/11.2 Safari/605.1.15

Steps to reproduce the problem:
1. https://gameboyessentials.com/1991/dmg-cn.html h2 in articles is my use of it (it displays the regular weight instead of the ultra thin of Avenir Next, which is a default installed font on all Apple systems)
2. https://stackoverflow.com/questions/22001035/font-weight-ignored-in-chrome#27704394 as a very thorough discussion of the problem

What is the expected behavior?
Using multiple @font-face to load a local font's different weights should work like on Safari and Firefox.

What went wrong?
Using multiple @font-face to assign different weights of the same font (in my case Avenir Next) to different font-weight and font-style. Font-style assignments work out of the box, but it seems that using a number stumps Chrome in assigning Ultra Thin to 100.

Did this work before? No 

Chrome version: <Copy from: 'about:version'>  Channel: stable
OS Version: OS X 10.13.3
Flash Version: