Fix for locked template

Author: ellatrix

packages/block-editor/src/components/rich-text/use-enter.js

@@ -70,11 +70,7 @@ export function useEnter( props ) {
 
 			const { text, start, end } = _value;
 
-			if ( event.shiftKey ) {
-				if ( ! disableLineBreaks ) {
-					onChange( insert( _value, '\n' ) );
-				}
-			} else if ( canSplit ) {
+			if ( canSplit ) {
 				splitValue( {
 					value: _value,
 					onReplace,

packages/block-editor/src/components/writing-flow/use-input.js

@@ -26,6 +26,8 @@ export default function useInput() {
 		__unstableIsSelectionMergeable,
 		hasMultiSelection,
 		getBlockName,
+		canInsertBlockType,
+		getBlockRootClientId,
 	} = useSelect( blockEditorStore );
 	const {
 		replaceBlocks,
@@ -57,18 +59,28 @@ export default function useInput() {
 					}
 
 					const clientId = getSelectedBlockClientId();
+					const blockName = getBlockName( clientId );
+
 					if (
 						! hasBlockSupport(
-							getBlockName( clientId ),
+							blockName,
 							'__experimentalOnEnter',
 							false
 						)
 					) {
 						return;
 					}
 
-					event.preventDefault();
-					__unstableSplitSelection();
+					// Ensure template is not locked.
+					if (
+						canInsertBlockType(
+							blockName,
+							getBlockRootClientId( clientId )
+						)
+					) {
+						__unstableSplitSelection();
+						event.preventDefault();
+					}
 				}
 				return;
 			}