The following function uses 'event' variable that does not exists.
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_shallIgnore: function (evt, keys) {
if (navigator.appVersion.indexOf('Mac')!=-1 && event.metaKey)
return;
....[Suppressed]...
},
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I believe it shall be using 'evt' instead as shown corrected below.
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_shallIgnore: function (evt, keys) {
if (navigator.appVersion.indexOf('Mac')!=-1 && evt.metaKey)
return;
....[Suppressed]...
},
----------------------------------------

We are using this _shallIgnore function for limiting user input keys on Textbox, Combobox, and etc.