You can specify attributes and values to these attributes when you initialize the array variable $cssPlugins. Example with the plugin //unpkg.com/leaflet@1.3.1/dist/leaflet.css having the attribute integrity with a value and the attribute crossorigin without any value:
Result in the DOM:
By the same way, you can specify attributes when you initialize $jsPlugins. Example with the plugin //unpkg.com/leaflet@1.3.1/dist/leaflet.js having the attribute integrity with a value and the attribute crossorigin without any value:
Result in the DOM: