About how the <file-pond> custom element functions in a form.
Form Behaviour
FilePond won’t affect the behavior of the form. When we submit the form it still synchronously posts any files selected in FilePond to the server.
Element Internals
The <file-pond> element implements ElementInternals, this means it behaves like a normal form element. Among others it has a value property, can trigger validation, and carries a reference to the parent form element.
Embeddeds styles
The <file-pond> element styles are embedded in the custom element, there’s no need to link a separate stylesheet.
Syncs input attributes
FilePond copies relevant attributes that are set on the file input element to the <file-pond> element, in the getting started guide that would be the required attribute.
The same happens the other way around. If the max-files attribute is present on the <file-pond> element and it has a value of '1' the multiple attribute on the internal input will be removed.
Acts as a component
When using <file-pond> in a plain HTML page we can set a limited selection of string based attributes on the <file-pond> element, other properties need to be set on the element reference.
When we’re using a JavaScript framework the <file-pond> custom element behaves like a component and properties can be set directly on the element <file-pond property={value}>.