For JavaScript related issues we need browser trace for troubleshooting. Follow the steps in this article for the developer tools in the browser you use: Google Chrome or Microsoft Edge (Chromium), Microsoft Edge (EdgeHTML), Apple Safari, or Firefox.
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Google Chrome and Microsoft Edge (Chromium) are both based on the Chromium open source project. The following steps show how to use the developer tools, which are very similar in the two browsers.
1- Sign in to Jira. It's important to sign in before you start the trace so that the trace doesn't contain sensitive information related to your sign-in.
2- Navigate to the step just prior to where the issue occurs.
3- Press F12 or select 
> More tools > Developer tools.
4- By default, the browser keeps trace information only for the page that's currently loaded. Set the following options so the browser keeps all trace information, even if your repro requires going to more than one page:
Select the Network tab, then select Preserve log.
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