npx hyperframes preview starts a long-lived next-server that keeps
chrome-headless-shell render workers resident. On GPU-less hosts (WSL,
containers, CI) each idle worker falls back to software WebGL (swiftshader)
and busy-spins a CPU core; a preview left open stacks these up until the
host is wedged. The skill never said preview was long-lived, so leaking
was the default outcome.
Add a Cleanup section + pitfall to SKILL.md and a Runaway CPU
troubleshooting entry with diagnose/fix/avoid steps.
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