Why does the Activity tab disappears on the app store connect web sometimes?
3 Answers
We can see the build info from TestFlight tab.
Select any build from TestFlight and then select Build Metadata tab. 
You can also access the tab by:
appstoreconnect.apple.com/apps/your-app-id-here/recent/activity/ios/builds?m=
reference: Developer Forums
P.S. The link trick works at the moment, but might not be permanent.
The Tab has moved recently (it's not a tab anymore). You can find it in the General section in the left navigation below Ratings and Reviews
Or you create the URL this way:
https://appstoreconnect.apple.com/apps/<app-id>/appstore/activity/ios/versions?m=
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