TLDR – The Add-SPShellAdmin and SPWebApplication.GrantAccessToProcessIdentity are very similar in what they do, but there are a few key differences: Add-SPShellAdmin: Should be used for granting admin accounts access to...
During an upgrade project we noticed that one of the pages that displays an InfoPath Form was throwing the error:
Object doesn’t support property or method ‘addEventLister’
This error wasn’t appearing anywhere else, so it was isolated to this specific page and also it worked in Chrome (The user was on IE 11). This led me to believe it was an IE 11 issue. I found the following post:
Adding the site to compatibility mode for IE 11 users fixed the issue..