Every asset in the frame answered 502. `fetch()` decompresses transparently
while `upstream.headers` still claims content-encoding: gzip, so re-emitting
those headers with the decompressed body hands the next hop a lie and it dies
with ZlibError.
The HTML escaped it only because the sidecar deletes that header when it
rewrites — which is why the page rendered and every stylesheet, script and
image beside it failed.
Not asking for compression removes the mismatch rather than chasing it through
two hops. The cost is nil: this hop is loopback, and the browser's own
connection is compressed by whatever terminates TLS.
officer
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