test: re-enable test for --headless=old (#27932)

system-tests/projects/e2e/cypress/e2e/headless_old.cy.js

@@ -1,9 +1,5 @@
 describe('e2e headless old spec', function () {
   it('has expected launch args', function () {
-    if (Cypress.isBrowser({ family: 'chromium' }) && Cypress.browserMajorVersion() >= 119) {
-      cy.fail('headless old is supported in Chromium >= 119, please update this system test.')
-    }
-    // TODO: re-enable this once https://bugs.chromium.org/p/chromium/issues/detail?id=1483163 is resolved
-    // cy.task('get:browser:args').should('contain', '--headless=old')
+    cy.task('get:browser:args').should('contain', '--headless=old')
   })
 })

system-tests/test/headless_old_spec.js

@@ -7,9 +7,7 @@ describe('e2e', () => {
     spec: 'headless_old.cy.js',
     browser: 'chrome',
     processEnv: {
-      // TODO: re-enable this once https://bugs.chromium.org/p/chromium/issues/detail?id=1483163
-      // has been resolved and we have updated to a version of Chromium that includes the fix
-      // CHROMIUM_USE_HEADLESS_OLD: 1,
+      CHROMIUM_USE_HEADLESS_OLD: 1,
     },
   })
 })