diff --git a/src/tests/editorOperationUtils/lockedCode.test.ts b/src/tests/editorOperationUtils/lockedCode.test.ts
index 0dc187e..0c07e01 100644
--- a/src/tests/editorOperationUtils/lockedCode.test.ts
+++ b/src/tests/editorOperationUtils/lockedCode.test.ts
@@ -356,4 +356,50 @@ function findLargest(numbers: number[]): number {
       text: ''
     })
   })
+
+  test('Handle all systems line break character', () => {
+    const model = createDefaultTestModel()
+    disposableStore.add(model)
+    const editor = monaco.editor.create(document.createElement('div'), {
+      model
+    })
+    disposableStore.add(editor)
+    disposableStore.add(lockCodeRanges(editor, {
+      getLockedRanges () {
+        return createDefaultTestLockedCodeRanges(model)
+      }
+    }))
+
+    const operationRange = createTestRange(model, 12, 22)
+    const operation = createTestOperation(operationRange,
+      '/* Ignore and do not change the code below */\n' +
+      '// toto\r\n' +
+      '/* Ignore and do not change the code above */\n' +
+      '\n' +
+      '// new comment\r\n' +
+      '// on two lines\r' +
+      '\n' +
+      '/* Ignore and do not change the code below */\r\n' +
+      '// toto\r' +
+      '/* Ignore and do not change the code above */\n' +
+      '\n' +
+      '// other comment\n'
+    )
+
+    const onDidChangeContent = jest.fn()
+    disposableStore.add(model.onDidChangeContent(onDidChangeContent))
+
+    editor.executeEdits(null, [operation])
+
+    expect(onDidChangeContent).toHaveBeenCalledTimes(1)
+    expect(onDidChangeContent.mock.calls[0]![0]).toMatchObject({
+      changes: [{
+        range: { startLineNumber: 21, startColumn: 1, endLineNumber: 22, endColumn: 24 },
+        text: '\n// other comment\n'
+      }, {
+        range: { startLineNumber: 15, startColumn: 1, endLineNumber: 17, endColumn: 1 },
+        text: '\n// new comment\n// on two lines'
+      }]
+    })
+  })
 })
diff --git a/src/tools.ts b/src/tools.ts
index 9684c8a..17219a5 100644
--- a/src/tools.ts
+++ b/src/tools.ts
@@ -177,7 +177,7 @@ export function lockCodeRanges (
   // Handle selection of the last line of an editable range
   disposableStore.add(
     editor.onDidChangeCursorSelection((e) => {
-      if (canEditRange(e.selection)) {
+      if (canEditRange(e.selection) || e.selection.isEmpty()) {
         return
       }
       const model = editor.getModel()
diff --git a/src/tools/utils/editorOperationUtils.ts b/src/tools/utils/editorOperationUtils.ts
index a3e4a6d..08f71c9 100644
--- a/src/tools/utils/editorOperationUtils.ts
+++ b/src/tools/utils/editorOperationUtils.ts
@@ -1,6 +1,7 @@
 import * as monaco from 'monaco-editor'
 import { ValidAnnotatedEditOperation } from 'vscode/vscode/vs/editor/common/model'
 import { excludeRanges } from './rangeUtils'
+import { normalizeStringLineBreaks } from './stringUtils'
 
 export class LockedCodeError extends Error {}
 
@@ -50,7 +51,7 @@ function tryIgnoreLockedCodeTextForOperation (
   const splitText: string[] = []
   const uneditableRangesText = uneditableRangesInOperationRange.map(range => model.getValueInRange(range))
   let currentRange: number = 0
-  let remainingText: string = operationText
+  let remainingText: string = normalizeStringLineBreaks(operationText, model.getEOL())
   while (remainingText.length > 0 && currentRange < uneditableRangesText.length) {
     const rangeText = uneditableRangesText[currentRange]
     if (rangeText != null && rangeText !== '') {
diff --git a/src/tools/utils/stringUtils.ts b/src/tools/utils/stringUtils.ts
new file mode 100644
index 0000000..ef235c2
--- /dev/null
+++ b/src/tools/utils/stringUtils.ts
@@ -0,0 +1,3 @@
+export function normalizeStringLineBreaks (str: string, lineBreakCharacter: string): string {
+  return str.replace(/\r\n|\r|\n/g, lineBreakCharacter)
+}