improve VRT test

packages/app/test/cypress/integration/2-basic-features/access-to-page.spec.ts

@@ -18,9 +18,11 @@ context('Access to page', () => {
 
   it('/Sandbox with anchor hash is successfully loaded', () => {
     cy.visit('/Sandbox#Headers');
-    cy.screenshot(`${ssPrefix}-sandbox-headers`, {
-      disableTimersAndAnimations: false,
-    });
+
+    // wait until opacity is 1.
+    cy.getByTestid('grw-fab-create-page').should('have.css', 'opacity', '1')
+
+    cy.screenshot(`${ssPrefix}-sandbox-headers`);
   });
 
   it('/Sandbox/Math is successfully loaded', () => {