Add multiple property — enables multi-file picker selection

package.json

@@ -1,6 +1,6 @@
 {
   "name": "@tp/tp-dropzone",
-  "version": "2.1.0",
+  "version": "2.1.1",
   "description": "",
   "main": "tp-dropzone.js",
   "scripts": {

tp-dropzone.js

@@ -36,13 +36,17 @@ class TpDropzone extends upload(dropzoneMixin(LitElement)) {
   render() {
     return html`
       <slot></slot>
-      <input type="file" @change=${this._handleFileSelect}>
+      <input type="file" ?multiple=${this.multiple} @change=${this._handleFileSelect}>
     `;
   }
 
   static get properties() {
     return {
       url: { type: String },
+      // Allow selecting several files in the picker dialog. The component's
+      // own "file-selected" event still reports the first file — read the
+      // change event's input.files for the full list.
+      multiple: { type: Boolean },
       isDraggedOn: { type: Boolean, reflect: true },
       file: { type: Object, state: true }
     };
@@ -51,6 +55,7 @@ class TpDropzone extends upload(dropzoneMixin(LitElement)) {
   constructor() {
     super();
     this.file = null;
+    this.multiple = false;
   }
 
   firstUpdated() {