diff --git a/scripts/e2e-diagram-scope.mjs b/scripts/e2e-diagram-scope.mjs
index eeba7da5020..43013476e32 100644
--- a/scripts/e2e-diagram-scope.mjs
+++ b/scripts/e2e-diagram-scope.mjs
@@ -20,7 +20,7 @@
  * Module usage:
  *   import { detectScope } from './e2e-diagram-scope.mjs';
  *   const spec = detectScope(['packages/mermaid/src/diagrams/flowchart/flowchart.ts']);
- *   // => 'e2e/rendering/flowchart/**'
+ *   // => 'e2e/rendering/flowchart/'
  */
 
 import { createInterface } from 'readline';
@@ -221,9 +221,10 @@ export function detectScope(files, options = {}) {
         break;
       }
 
-      // File inside a diagram subfolder → scope to that subfolder.
+      // File inside a diagram subfolder → scope to that subfolder. Playwright
+      // treats CLI filters as regular expressions, so keep this glob-free.
       const subFolder = rest.slice(0, slashIdx);
-      directlyChangedSpecs.push(`${specFolderPrefix}${subFolder}/**`);
+      directlyChangedSpecs.push(`${specFolderPrefix}${subFolder}/`);
       continue;
     }
 
@@ -254,7 +255,8 @@ export function detectScope(files, options = {}) {
     return '';
   }
 
-  // Build spec patterns from diagram names using filesystem discovery
+  // Build regular-expression-safe spec patterns from diagram names using
+  // filesystem discovery. A trailing slash matches every file in the folder.
   const specs = new Set(directlyChangedSpecs);
 
   /** @type {Set<string> | null} */
@@ -277,7 +279,7 @@ export function detectScope(files, options = {}) {
   for (const name of diagramNames) {
     const folder = `${specBaseDir}/${name}`;
     if (existsSync(folder)) {
-      specs.add(`${folder}/**`);
+      specs.add(`${folder}/`);
     } else if (hasFixtures(name)) {
       // Fixtures-only diagram (no per-diagram spec subfolder) — the global mmd
       // snapshot runner exercises it.
diff --git a/scripts/e2e-diagram-scope.spec.ts b/scripts/e2e-diagram-scope.spec.ts
index 5e25eee1923..9e87f00c825 100644
--- a/scripts/e2e-diagram-scope.spec.ts
+++ b/scripts/e2e-diagram-scope.spec.ts
@@ -20,12 +20,20 @@ describe('detectScope', () => {
     ]);
     expect(result.split(',')).toEqual(
       expect.arrayContaining([
-        `${SPEC_BASE_DIR}/flowchart/**`,
+        `${SPEC_BASE_DIR}/flowchart/`,
         `${SPEC_BASE_DIR}/mmd-snapshots.spec.ts`,
       ])
     );
   });
 
+  it('returns patterns that Playwright can compile as regular expressions', () => {
+    const result = detectScope(['packages/mermaid/src/diagrams/sequence/sequenceRenderer.ts']);
+
+    for (const pattern of result.split(',')) {
+      expect(() => new RegExp(pattern, 'gi')).not.toThrow();
+    }
+  });
+
   it('falls back to full suite when rendering-util is touched', () => {
     expect(
       detectScope([
@@ -66,8 +74,8 @@ describe('detectScope', () => {
     ]);
     expect(result.split(',')).toEqual(
       expect.arrayContaining([
-        `${SPEC_BASE_DIR}/gantt/**`,
-        `${SPEC_BASE_DIR}/pie/**`,
+        `${SPEC_BASE_DIR}/gantt/`,
+        `${SPEC_BASE_DIR}/pie/`,
         `${SPEC_BASE_DIR}/mmd-snapshots.spec.ts`,
       ])
     );
@@ -85,7 +93,7 @@ describe('detectScope', () => {
     ]);
     expect(result.split(',')).toEqual(
       expect.arrayContaining([
-        `${SPEC_BASE_DIR}/flowchart/**`,
+        `${SPEC_BASE_DIR}/flowchart/`,
         `${SPEC_BASE_DIR}/mmd-snapshots.spec.ts`,
       ])
     );
@@ -112,10 +120,7 @@ describe('detectScope', () => {
   it('scopes to the subfolder when a spec file in that subfolder is modified', () => {
     const result = detectScope([`${SPEC_BASE_DIR}/gantt/gantt.spec.js`]);
     expect(result.split(',')).toEqual(
-      expect.arrayContaining([
-        `${SPEC_BASE_DIR}/gantt/**`,
-        `${SPEC_BASE_DIR}/mmd-snapshots.spec.ts`,
-      ])
+      expect.arrayContaining([`${SPEC_BASE_DIR}/gantt/`, `${SPEC_BASE_DIR}/mmd-snapshots.spec.ts`])
     );
   });
 
@@ -136,7 +141,7 @@ describe('detectScope', () => {
       `${SPEC_BASE_DIR}/gantt/gantt.spec.js`,
     ]);
     // Both point to the same subfolder — should deduplicate
-    expect(result.split(',').filter((s) => s === `${SPEC_BASE_DIR}/gantt/**`).length).toBe(1);
+    expect(result.split(',').filter((s) => s === `${SPEC_BASE_DIR}/gantt/`).length).toBe(1);
   });
 });
 
@@ -183,7 +188,7 @@ describe('ignorable files (docs-only, changesets, etc.)', () => {
     ]);
     expect(result.split(',')).toEqual(
       expect.arrayContaining([
-        `${SPEC_BASE_DIR}/flowchart/**`,
+        `${SPEC_BASE_DIR}/flowchart/`,
         `${SPEC_BASE_DIR}/mmd-snapshots.spec.ts`,
       ])
     );
@@ -196,7 +201,7 @@ describe('ignorable files (docs-only, changesets, etc.)', () => {
     ]);
     expect(result.split(',')).toEqual(
       expect.arrayContaining([
-        `${SPEC_BASE_DIR}/flowchart/**`,
+        `${SPEC_BASE_DIR}/flowchart/`,
         `${SPEC_BASE_DIR}/mmd-snapshots.spec.ts`,
       ])
     );