backstage/.changeset/new-nails-thank.md

@backstage/plugin-proxy-backend

@backstage/plugin-proxy-backend
patch

Filter the headers that are sent from the proxied-targed back to the frontend to not forwarded unwanted authentication or monitoring contexts from other origins (like Set-Cookie with e.g. a google analytics context). The implementation reuses the allowedHeaders configuration that now controls both directions frontend->target and target->frontend.