Reverted Untrusted submit event can no longer trigger form submission

Published: | Categories: DOM


Previously, Firefox allowed to submit a <form> through an untrusted submit event generated in a script, not by the user. This Firefox-specific behaviour has been removed with Firefox 69, aiming at improve web interoperability.

// Don't do this
form.dispatchEvent(new Event('submit'));
// Do this

However, the form submit button in YUI 2 is broken due to the change, because it relies on a user-agent detection to call the submit method only in Chrome, Safari and Internet Explorer. Mozilla is trying to work around the issue on Jenkins that uses YUI, but the chance is, other sites are also affected. If your site still uses the legacy library, you can patch the code in question just like what the Jenkins team did.

Update: The change has been backed out due to the compatibility concerns.