isnetweb ui  is loading the file IEMozBridge.js to support old and deprecated versions of IE and FF.

For example the file loads function document.createStyleSheet.

Meaning that any other browser (except for IE) is not supposed to have such method at all.
and our web site doesn't support IE but Chrome,

Is file IEMozBridge.js still required or is it a legacy file that may be deprecated/removed?