I am trying to load the css files (bootstrap + my main.css) of my site at the bottom of the page instead of the top. I have inlined the style I need for the content above the fold.
For the Js I had no issue using the POS_END position option.
Seems like you have to write some Javascript to load CSS files in a non-blocking way and it’s not built into yii\web\View. Might be worth a feature request.
