@Ahsan Abbas Welcome to Microsoft Q & A Community Forum. We noticed similar issue occurring for various customers and based on the information gathered , posting same information here for benefit of broader community.
Post review with our internal team, it was called out that this could be similar to the Ad blocker issue, JS files of format highlighted are being blocked by ad blockers. One of the workaround which is helping is by disabling the Adblockers for the browsers. So please try this out , in case you are getting into this issue.
Seems that just disabling adblock specific sites (azure portal in this case) in most adblock extensions is not helping fix it. Have to disable adblock at browser level.
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