To reproduce, open https://en.wikipedia.beta.wmflabs.org/
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If you report this error to the Wikimedia System Administrators, please include the details below.
Request from - via deployment-cache-text06.deployment-prep.eqiad.wmflabs, ATS/8.0.8
Error: 502, Next Hop Connection Failed at 2020-11-09 12:56:10 GMT