I believe we are using a vanilla version of JIRA 7.11.0, with no additional plugins. When looking at an issue, if I select "More v" --> "Agile Board" (shown below), the loading screen starts but does not finish.

I pulled up the Console with F12, and the following error was present:
Uncaught TypeError: Cannot redefine property: contextPath
at Function.defineProperty (<anonymous>)
at eval (eval at <anonymous> (batch.js:59), <anonymous>:37:16)
at eval (eval at <anonymous> (batch.js:59), <anonymous>:49:7)
at eval (<anonymous>)
at batch.js:59
at Function.globalEval (batch.js:59)
at HTMLScriptElement.<anonymous> (batch.js:171)
at Function.each (batch.js:60)
at init.domManip (batch.js:170)
at init.append (batch.js:165)
Does anyone know what could be causing this issue, or how to resolve it?
Thank you,
James