Brief title: Bug: no key binding of custom menu
Steps to reproduce the issue: Adding a (sub)menu item through javascript API e.g. app.addSubMenu('CustomScripts', '', 'File', 0)
Environment (OS, other related application versions, etc.): Windows 7 running Acrobat 2019.008.20081
Expected result: An alphanumeric key binds to the item name. In the example above, since "C" is binds to Close of File menu item, binding of "u" is expected to the custom menu item named "CustomScripts"
Observed result: No alphanumeric key binding. A user using keyboard can only navigate through arrows, which is tedious and not accessible friendly.