const enabled = process.browser && performance.mark && ( process.env.NODE_ENV !== 'production' || (typeof location !== 'undefined' && location.search.includes('marks=true')) ) const perf = process.browser && performance export function mark (name) { if (enabled) { perf.mark(`start ${name}`) } } export function stop (name) { if (enabled) { perf.mark(`end ${name}`) perf.measure(name, `start ${name}`, `end ${name}`) } }