frontend: ignore drop event in form, trigger upload instead of file input dialog (fixes #74, maybe)

frontend/src/components/FileDrop.tsx

@@ -160,6 +160,7 @@ export default class FileDrop extends React.PureComponent<FileDropProps, FileDro
   }
 
   handleDrop: ReactDragEventHandler<HTMLDivElement> = (event) => {
+    event.preventDefault?.()
     if (this.props.onDrop && FileDrop.eventHasFiles(event)) {
       const files = event.dataTransfer ? event.dataTransfer.files : null
       this.props.onDrop(files, event)

frontend/src/components/FileUploadField.tsx

@@ -18,6 +18,8 @@ export default function FileUploadField({onSelect: onSelect_, multiple}) {
   )
 
   function onChangeField(e) {
+    e.preventDefault?.()
+
     if (e.target.files && e.target.files.length) {
       onSelect(e.target.files)
     }