It seems I'm dumb or fonts don't like me.
After installing some fonts, specifically Igna Sans, I've noticed on both ends of the size spectrum, very thin or very thick fonts don't work. They show up with a "weight=xxx" name instead of their actual name. Choosing them just seem to default to the last font style chosen. I've double checked to make sure they are installed on the system and they are, they are working in other programs such as Word and Notepad. Why aren't they working in Inkscape?
Currently on 0.92.2 and Windows 10. Fonts are installed in the default Windows font folder.
The "weight=250" option should be "Extra Light"