2 files changed, 13 insertions, 2 deletions
diff --git a/activestorage/app/javascript/activestorage/file_checksum.js b/activestorage/app/javascript/activestorage/file_checksum.js
index ffaec1a128..a9dbef69ea 100644
--- a/activestorage/app/javascript/activestorage/file_checksum.js
+++ b/activestorage/app/javascript/activestorage/file_checksum.js
@@ -39,7 +39,7 @@ export class FileChecksum {
   }
 
   readNextChunk() {
-    if (this.chunkIndex < this.chunkCount) {
+    if (this.chunkIndex < this.chunkCount || (this.chunkIndex == 0 && this.chunkCount == 0)) {
       const start = this.chunkIndex * this.chunkSize
       const end = Math.min(start + this.chunkSize, this.file.size)
       const bytes = fileSlice.call(this.file, start, end)
diff --git a/activestorage/app/javascript/activestorage/ujs.js b/activestorage/app/javascript/activestorage/ujs.js
index 08c535470d..f5353389ef 100644
--- a/activestorage/app/javascript/activestorage/ujs.js
+++ b/activestorage/app/javascript/activestorage/ujs.js
@@ -2,16 +2,25 @@ import { DirectUploadsController } from "./direct_uploads_controller"
 import { findElement } from "./helpers"
 
 const processingAttribute = "data-direct-uploads-processing"
+const submitButtonsByForm = new WeakMap
 let started = false
 
 export function start() {
   if (!started) {
     started = true
+    document.addEventListener("click", didClick, true)
     document.addEventListener("submit", didSubmitForm)
     document.addEventListener("ajax:before", didSubmitRemoteElement)
   }
 }
 
+function didClick(event) {
+  const { target } = event
+  if (target.tagName == "INPUT" && target.type == "submit" && target.form) {
+    submitButtonsByForm.set(target.form, target)
+  }
+}
+
 function didSubmitForm(event) {
   handleFormSubmissionEvent(event)
 }
@@ -49,7 +58,8 @@ function handleFormSubmissionEvent(event) {
 }
 
 function submitForm(form) {
-  let button = findElement(form, "input[type=submit]")
+  let button = submitButtonsByForm.get(form) || findElement(form, "input[type=submit]")
+
   if (button) {
     const { disabled } = button
     button.disabled = false
@@ -64,6 +74,7 @@ function submitForm(form) {
     button.click()
     form.removeChild(button)
   }
+  submitButtonsByForm.delete(form)
 }
 
 function disable(input) {