Hit both today doing a live QA pass on the gateway: plain
nixpkgs#chromium has no color-emoji font (tofu boxes read exactly
like a missing-icon bug), and a page whose content loads async after
the initial paint (SSE, fetch-on-mount) screenshots as a bare
"loading..." placeholder without --virtual-time-budget. Neither is a
real product bug, but both need a documented fix for when an accurate
render actually matters, not just "know to discount it."
Captures a lesson from this session: "no browser in this container"
usually means no browser pre-installed, not unreachable. nixpkgs#chromium
is a `nix shell` away and one headless invocation renders a page +
writes a PNG, no puppeteer/playwright needed for a static screenshot.
Every agent hits "I have no browser" sooner or later when reviewing a
frontend change; this has been rediscovered independently across
several sessions rather than remembered. Belongs in base (every agent
needs it, not role-specific) alongside the sibling skills already
there.
