CONSOLE MESSAGE: line 17: 1 CONSOLE MESSAGE: line 17: 2 CONSOLE MESSAGE: line 17: 3 This test should trigger 'window.onerror' for the exception in the attribute handler, regardless of how it's set. On success, you will see a series of "PASS" messages, followed by "TEST COMPLETE". window.onerror: "Uncaught TypeError: Cannot read property 'mu' of null" at window-onerror-12.html (Line: 12, Column: 37) Stack Trace: TypeError: Cannot read property 'mu' of null at HTMLButtonElement.onclick window-onerror-12.html:12:37 at window-onerror-12.html:33:24 Returning 'true': the error should not be reported in the console as an unhandled exception. window.onerror: "Uncaught TypeError: Cannot read property 'mu' of null" at window-onerror-12.html (Line: 35, Column: 18) Stack Trace: TypeError: Cannot read property 'mu' of null at HTMLButtonElement.onclick window-onerror-12.html:35:18 at window-onerror-12.html:33:24 Returning 'true': the error should not be reported in the console as an unhandled exception. window.onerror: "Uncaught TypeError: Cannot read property 'mu' of null" at window-onerror-12.html (Line: 35, Column: 18) Stack Trace: TypeError: Cannot read property 'mu' of null at HTMLButtonElement.onclick window-onerror-12.html:35:18 at window-onerror-12.html:33:24 Returning 'true': the error should not be reported in the console as an unhandled exception. PASS successfullyParsed is true TEST COMPLETE Button. Button 2 Button 3