--- a/content/html/content/src/HTMLMediaElement.cpp
+++ b/content/html/content/src/HTMLMediaElement.cpp
@@ -2928,16 +2928,21 @@ void HTMLMediaElement::MetadataLoaded(co
   // delete the VideoFrameContainer. This happens when the src is changed to an
   // audio only file.
   if (!aInfo->HasVideo() && mVideoFrameContainer) {
     // call ForgetElement() such that callbacks from |mVideoFrameContainer|
     // won't reach us anymore.
     mVideoFrameContainer->ForgetElement();
     mVideoFrameContainer = nullptr;
   }
+
+  if (IsVideo()) {
+    // Update the screen wakelock in case mHasVideo changed
+    NotifyOwnerDocumentActivityChanged();
+  }
 }
 
 void HTMLMediaElement::FirstFrameLoaded()
 {
   NS_ASSERTION(!mSuspendedAfterFirstFrame, "Should not have already suspended");
 
   ChangeDelayLoadStatus(false);
   UpdateReadyStateForData(NEXT_FRAME_UNAVAILABLE);