diff --git a/editor/libeditor/HTMLEditor.cpp b/editor/libeditor/HTMLEditor.cpp
index 6a630cb1c4..130b033bd1 100644
--- a/editor/libeditor/HTMLEditor.cpp
+++ b/editor/libeditor/HTMLEditor.cpp
@@ -664,8 +664,7 @@ HTMLEditor::HandleKeyPressEvent(nsIDOMKeyEvent* aKeyEvent)
       return TypedText(NS_LITERAL_STRING("\t"), eTypedText);
     }
     case NS_VK_RETURN:
-      if (nativeKeyEvent->IsControl() || nativeKeyEvent->IsAlt() ||
-          nativeKeyEvent->IsMeta() || nativeKeyEvent->IsOS()) {
+      if (!nativeKeyEvent->IsInputtingLineBreak()) {
         return NS_OK;
       }
       aKeyEvent->AsEvent()->PreventDefault(); // consumed
@@ -677,11 +676,7 @@ HTMLEditor::HandleKeyPressEvent(nsIDOMKeyEvent* aKeyEvent)
       return TypedText(EmptyString(), eTypedBreak);
   }
 
-  // NOTE: On some keyboard layout, some characters are inputted with Control
-  // key or Alt key, but at that time, widget sets FALSE to these keys.
-  if (!nativeKeyEvent->mCharCode || nativeKeyEvent->IsControl() ||
-      nativeKeyEvent->IsAlt() || nativeKeyEvent->IsMeta() ||
-      nativeKeyEvent->IsOS()) {
+  if (!nativeKeyEvent->IsInputtingText()) {
     // we don't PreventDefault() here or keybindings like control-x won't work
     return NS_OK;
   }
diff --git a/editor/libeditor/TextEditor.cpp b/editor/libeditor/TextEditor.cpp
index 3bee7843ce..4b26eff9cd 100644
--- a/editor/libeditor/TextEditor.cpp
+++ b/editor/libeditor/TextEditor.cpp
@@ -397,20 +397,14 @@ TextEditor::HandleKeyPressEvent(nsIDOMKeyEvent* aKeyEvent)
       return TypedText(NS_LITERAL_STRING("\t"), eTypedText);
     }
     case NS_VK_RETURN:
-      if (IsSingleLineEditor() || nativeKeyEvent->IsControl() ||
-          nativeKeyEvent->IsAlt() || nativeKeyEvent->IsMeta() ||
-          nativeKeyEvent->IsOS()) {
+      if (IsSingleLineEditor() || !nativeKeyEvent->IsInputtingLineBreak()) {
         return NS_OK;
       }
       aKeyEvent->AsEvent()->PreventDefault();
       return TypedText(EmptyString(), eTypedBreak);
   }
 
-  // NOTE: On some keyboard layout, some characters are inputted with Control
-  // key or Alt key, but at that time, widget sets FALSE to these keys.
-  if (!nativeKeyEvent->mCharCode || nativeKeyEvent->IsControl() ||
-      nativeKeyEvent->IsAlt() || nativeKeyEvent->IsMeta() ||
-      nativeKeyEvent->IsOS()) {
+  if (!nativeKeyEvent->IsInputtingText()) {
     // we don't PreventDefault() here or keybindings like control-x won't work
     return NS_OK;
   }
diff --git a/modules/libpref/init/all.js b/modules/libpref/init/all.js
index ec8e6d770f..ec30c9d4b2 100644
--- a/modules/libpref/init/all.js
+++ b/modules/libpref/init/all.js
@@ -231,6 +231,10 @@ pref("dom.keyboardevent.code.enabled", true);
 // even if this is true).
 pref("dom.keyboardevent.dispatch_during_composition", false);
 
+// If this is true, TextEventDispatcher dispatches keypress events
+// for the input of non-printable characters (content only).
+pref("dom.keyboardevent.keypress.dispatch_non_printable_in_content", false);
+
 // Whether URL,Location,Link::GetHash should be percent encoded
 // in setter and percent decoded in getter (old behaviour = true)
 pref("dom.url.encode_decode_hash", true);
diff --git a/widget/TextEventDispatcher.cpp b/widget/TextEventDispatcher.cpp
index 6c54376a48..2b058ba9c3 100644
--- a/widget/TextEventDispatcher.cpp
+++ b/widget/TextEventDispatcher.cpp
@@ -21,6 +21,7 @@ namespace widget {
  *****************************************************************************/
 
 bool TextEventDispatcher::sDispatchKeyEventsDuringComposition = false;
+bool TextEventDispatcher::sDispatchKeyPressEventNonPrintableInContent = false;
 
 TextEventDispatcher::TextEventDispatcher(nsIWidget* aWidget)
   : mWidget(aWidget)
@@ -36,6 +37,10 @@ TextEventDispatcher::TextEventDispatcher(nsIWidget* aWidget)
       &sDispatchKeyEventsDuringComposition,
       "dom.keyboardevent.dispatch_during_composition",
       false);
+    Preferences::AddBoolVarCache(
+      &sDispatchKeyPressEventNonPrintableInContent,
+      "dom.keyboardevent.keypress.dispatch_non_printable_in_content",
+      false);
     sInitialized = true;
   }
 }
@@ -531,6 +536,13 @@ TextEventDispatcher::DispatchKeyboardEventInternal(
     }
   }
 
+  if (!sDispatchKeyPressEventNonPrintableInContent &&
+      keyEvent.mMessage == eKeyPress &&
+      !keyEvent.IsInputtingText() &&
+      !keyEvent.IsInputtingLineBreak()) {
+    keyEvent.mFlags.mOnlySystemGroupDispatchInContent = true;
+  }
+
   DispatchInputEvent(mWidget, keyEvent, aStatus);
   return true;
 }
diff --git a/widget/TextEventDispatcher.h b/widget/TextEventDispatcher.h
index 1bed15a3bf..6d28200f5f 100644
--- a/widget/TextEventDispatcher.h
+++ b/widget/TextEventDispatcher.h
@@ -399,6 +399,10 @@ private:
   // is a composition.
   static bool sDispatchKeyEventsDuringComposition;
 
+  // If this is true, keypress events for non-printable keys are dispatched to
+  // event listeners of the system event group in web content.
+  static bool sDispatchKeyPressEventNonPrintableInContent;
+
   nsresult BeginInputTransactionInternal(
              TextEventDispatcherListener* aListener,
              InputTransactionType aType);
diff --git a/widget/TextEvents.h b/widget/TextEvents.h
index 6c29341144..59aa91b2e0 100644
--- a/widget/TextEvents.h
+++ b/widget/TextEvents.h
@@ -183,6 +183,30 @@ public:
     return IsKeyEventOnPlugin(mMessage);
   }
 
+  bool IsInputtingText() const
+  {
+    // NOTE: On some keyboard layouts, some characters are put in with Control
+    //       or Alt keys, but at that time, widget unsets the modifier flag
+    //       from the eKeyPress event, so it does not count as a modifier in
+    //       this check.
+    return mMessage == eKeyPress &&
+           mCharCode &&
+           !(mModifiers & (MODIFIER_ALT |
+                           MODIFIER_CONTROL |
+                           MODIFIER_META |
+                           MODIFIER_OS));
+  }
+
+  bool IsInputtingLineBreak() const
+  {
+    return mMessage == eKeyPress &&
+           mKeyNameIndex == KEY_NAME_INDEX_Enter &&
+           !(mModifiers & (MODIFIER_ALT |
+                           MODIFIER_CONTROL |
+                           MODIFIER_META |
+                           MODIFIER_OS));
+  }
+
   virtual WidgetEvent* Duplicate() const override
   {
     MOZ_ASSERT(mClass == eKeyboardEventClass,