Wait for image to be rendered

cypress/integration/other/configuration.spec.js

@@ -118,8 +118,8 @@ describe('Configuration', () => {
     it('should not taint the initial configuration when using multiple directives', () => {
       const url = 'http://localhost:9000/regression/issue-1874.html';
       cy.visit(url);
-
-      cy.get('svg');
+      cy.window().should('have.property', 'rendered', true);
+      cy.get('svg').should('be.visible');
       cy.matchImageSnapshot(
         'configuration.spec-should-not-taint-initial-configuration-when-using-multiple-directives'
       );

cypress/platform/regression/issue-1874.html

@@ -21,7 +21,11 @@ sequenceDiagram
     mermaid.initialize({
       theme: 'base',
       themeVariables: {},
-      startOnLoad: true,
+      startOnLoad: false,
     });
+    await mermaid.run();
+    if (window.Cypress) {
+      window.rendered = true;
+    }
   </script>
 </html>