Enable form.requestSubmit(). This was fully implemented via Bug 197958 and it passes the WPT tests but we never actually enabled it.
Created attachment 449448 [details] Patch
Committed r288179 (246160@main): <https://commits.webkit.org/246160@main> All reviewed patches have been landed. Closing bug and clearing flags on attachment 449448 [details].
<rdar://problem/87748810>
*** Bug 235947 has been marked as a duplicate of this bug. ***