Or you could just add a less file in your plugin and add it to the less array in plugin.json
Are custom skin possible? I see right now it's just loading https://bootswatch.com.
Was wondering if there's a way to modify one of those skins and have it be an option on the site.
@dangeruss It is possible. You will have to either fork persona to add in your changes or make a new theme.
If you need an example of how custom skins can be applied to the theme you can check these 2 themes.
You can even follow these examples to add a modified version of an existing bootswatch skin.