Our E2E test environment is deployed with mTLS, but it's impractical
for us to use mTLS in headless browsers for automated testing (or even
in manual testing). Provide certificates for proxying the web UI via
Nginx. This proxy uses client certs for proxying to the HTTP endpoint
and a self-signed cert for the browser-facing endpoint. We can accept
certificate errors in the automated tests we'll be adding in the next
step of this work.
