diff --git a/app.js b/app.js
index a04aae71..bacbb51f 100644
--- a/app.js
+++ b/app.js
@@ -87,7 +87,7 @@ const CSV_HEADERS = [
   '스프린트',
   '스토리포인트'
 ];
-const CSV_FORMULA_PREFIX_PATTERN = /^\s*[=+\-@|]/;
+const CSV_FORMULA_PREFIX_PATTERN = /^\s*[=+\-@|＝＋－＠｜]/;
 const UNSAFE_JSON_KEYS = new Set(['__proto__', 'constructor', 'prototype']);
 
 const CSV_FIELD_LABELS = Object.freeze(Object.assign(Object.create(null), {
@@ -790,6 +790,9 @@ function renderEditorRow(anchorId) {
   panel.className = 'editor-panel';
   const form = document.createElement('form');
   form.dataset.editorForm = 'true';
+  // ScopeWeave validation is the sole persistence gate; native constraint
+  // validation would intercept submission and move focus before saveEditor().
+  form.noValidate = true;
   const editorGrid = document.createElement('div');
   editorGrid.className = 'editor-grid';
 
@@ -1068,7 +1071,13 @@ function renderEditorValidation() {
 
   const saveButton = form.querySelector('button[type="submit"]');
   if (saveButton) {
-    saveButton.disabled = errors.length > 0;
+    if (errors.length > 0) {
+      saveButton.setAttribute('aria-disabled', 'true');
+      saveButton.setAttribute('aria-describedby', 'editor-errors');
+    } else {
+      saveButton.removeAttribute('aria-disabled');
+      saveButton.removeAttribute('aria-describedby');
+    }
     saveButton.title = errors.length > 0 ? '입력값을 올바르게 수정해야 저장할 수 있습니다.' : '저장 (Enter)';
   }
 
diff --git a/package.json b/package.json
index 8cefdc74..4b9c6d14 100644
--- a/package.json
+++ b/package.json
@@ -18,7 +18,7 @@
     "test:coverage:cases": "node tests/unit/coverage-script-contract.test.mjs && node tests/unit/attachment-status.test.mjs && node tests/unit/clearfolio-status-signal.test.mjs && node tests/unit/clearfolio-adapter-mock-hmac.test.mjs && node tests/unit/orchestrator.test.mjs && node tests/unit/orchestrator-coverage.test.mjs && node tests/unit/orchestrator-attribution.test.mjs && node tests/unit/msproject.test.mjs && node tests/unit/auth-password.test.mjs && node tests/unit/editor-unsaved.test.mjs && node tests/unit/static-coverage-evidence.test.mjs && npm run test:api",
     "test:e2e": "playwright test",
     "test:e2e:headed": "playwright test --headed",
-    "test:e2e:cloud": "playwright install chromium && playwright test tests/e2e/cloud.spec.js tests/e2e/toast-accessibility.spec.js",
+    "test:e2e:cloud": "playwright install chromium && playwright test tests/e2e/cloud.spec.js tests/e2e/toast-accessibility.spec.js tests/e2e/editor-validation-synchronization.spec.js",
     "test:fuzz": "playwright install chromium && playwright test tests/e2e/csv_formula_fuzz.spec.js",
     "fuzz": "node --test tests/fuzz/*.mjs"
   },
diff --git a/tests/e2e/csv_formula_fuzz.spec.js b/tests/e2e/csv_formula_fuzz.spec.js
index 5ff20a48..d1ffd7bc 100644
--- a/tests/e2e/csv_formula_fuzz.spec.js
+++ b/tests/e2e/csv_formula_fuzz.spec.js
@@ -1,6 +1,8 @@
 import { test, expect } from '@playwright/test';
 import fc from 'fast-check';
 
+const DANGEROUS_CSV_PREFIX_PATTERN = /^\s*[=+\-@|＝＋－＠｜]/;
+
 test.describe('CSV formula fuzzing', () => {
   test.beforeEach(async ({ page }) => {
     await page.goto('./');
@@ -14,16 +16,35 @@ test.describe('CSV formula fuzzing', () => {
           sanitized: window.sanitizeCsvFormulaValue(value)
         }), candidate);
         const normalized = String(candidate ?? '');
-        const dangerous = /^\s*[=+\-@|]/.test(normalized);
+        const dangerous = DANGEROUS_CSV_PREFIX_PATTERN.test(normalized);
         const expectedSanitized = dangerous ? `'${normalized}` : normalized;
 
         expect(result.sanitized).toBe(expectedSanitized);
         expect(result.escaped.startsWith('"')).toBe(true);
         expect(result.escaped.endsWith('"')).toBe(true);
         expect(result.escaped.slice(1, -1).replace(/""/g, '"')).toBe(expectedSanitized);
-        expect(/^\s*[=+\-@|]/.test(result.sanitized)).toBe(false);
+        expect(DANGEROUS_CSV_PREFIX_PATTERN.test(result.sanitized)).toBe(false);
       }),
       { numRuns: 100, seed: 20260709 }
     );
   });
-});
+
+  test('neutralizes fullwidth formula-prefix compatibility characters', async ({ page }) => {
+    const compatibilityPrefixes = ['＝', '＋', '－', '＠', '｜'];
+
+    for (const prefix of compatibilityPrefixes) {
+      for (const candidate of [`${prefix}1+1`, ` \t${prefix}SUM(A1:A2)`]) {
+        const result = await page.evaluate((value) => ({
+          escaped: window.csvEscape(value),
+          sanitized: window.sanitizeCsvFormulaValue(value)
+        }), candidate);
+        const expectedSanitized = `'${candidate}`;
+
+        expect(result.sanitized).toBe(expectedSanitized);
+        expect(result.escaped.startsWith('"')).toBe(true);
+        expect(result.escaped.endsWith('"')).toBe(true);
+        expect(result.escaped.slice(1, -1).replace(/""/g, '"')).toBe(expectedSanitized);
+      }
+    }
+  });
+});
\ No newline at end of file
diff --git a/tests/e2e/editor-validation-synchronization.spec.js b/tests/e2e/editor-validation-synchronization.spec.js
new file mode 100644
index 00000000..cff9b985
--- /dev/null
+++ b/tests/e2e/editor-validation-synchronization.spec.js
@@ -0,0 +1,58 @@
+import { test, expect } from '@playwright/test';
+
+async function openRootEditor(page) {
+  await page.goto('./');
+  const initialTaskCount = await page.locator('tbody tr[data-task-id]').count();
+  await page.getByRole('button', { name: '최상위 작업 추가' }).click();
+  const editor = page.locator('.editor-panel');
+  const phaseInput = page.getByTestId('editor-phase');
+  const saveButton = editor.getByRole('button', { name: '저장', exact: true });
+  await expect(editor).toBeVisible();
+  return { initialTaskCount, editor, phaseInput, saveButton };
+}
+
+test('valid final edit can submit immediately without waiting for debounced validation', async ({ page }) => {
+  const { initialTaskCount, editor, phaseInput, saveButton } = await openRootEditor(page);
+
+  await expect(saveButton).toHaveJSProperty('disabled', false);
+  await expect(saveButton).toHaveAttribute('aria-disabled', 'true');
+  await expect(saveButton).toHaveAttribute('aria-describedby', 'editor-errors');
+
+  await phaseInput.fill('P9000.즉시 저장 검증');
+  await saveButton.evaluate((button) => button.click());
+
+  await expect(editor).toHaveCount(0);
+  await expect(page.locator('tbody tr[data-task-id]')).toHaveCount(initialTaskCount + 1);
+});
+
+test('Enter after the final required edit submits against the latest draft', async ({ page }) => {
+  const { initialTaskCount, editor, phaseInput } = await openRootEditor(page);
+
+  await phaseInput.fill('P9001.키보드 즉시 저장');
+  await phaseInput.press('Enter');
+
+  await expect(editor).toHaveCount(0);
+  await expect(page.locator('tbody tr[data-task-id]')).toHaveCount(initialTaskCount + 1);
+});
+
+test('invalid immediate activation stays focusable, refreshes errors, and persists nothing', async ({ page }) => {
+  const { initialTaskCount, editor, phaseInput, saveButton } = await openRootEditor(page);
+
+  await phaseInput.fill('P9002.유효 상태');
+  await expect(saveButton).not.toHaveAttribute('aria-disabled', 'true');
+  await expect(saveButton).not.toHaveAttribute('aria-describedby', 'editor-errors');
+
+  await phaseInput.fill('');
+  await saveButton.evaluate((button) => {
+    button.focus();
+    button.click();
+  });
+
+  await expect(editor).toBeVisible();
+  await expect(page.locator('tbody tr[data-task-id]')).toHaveCount(initialTaskCount);
+  await expect(saveButton).toHaveJSProperty('disabled', false);
+  await expect(saveButton).toBeFocused();
+  await expect(saveButton).toHaveAttribute('aria-disabled', 'true');
+  await expect(saveButton).toHaveAttribute('aria-describedby', 'editor-errors');
+  await expect(page.locator('#editor-errors')).toContainText('최상위 작업은 단계 값을 입력해야 합니다.');
+});