Add Collection more flexible

[simoco0781]

I'm using the "addCollection in a StandardLayout".
I success to save/delete from the StorageLocator and make it appear and draggable from the aside panel.
But I have no control on the EmailEditorProvider onAddCollection method.
I wish to generate a thumbnail (via an html2canvas) instead of uploading an image from the modal.
Actually "title", "description" and "image" are required..

Is it possible, in a 1st time to change it, at least make the image not required ? (and for a next step why not add the possibility to pass values for exemple to send thumbnail generated via an html2canvas)

Thx a lot