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Entry #13 of UpFork’s ledger · A lesson's version: A still frame drawn on a worker's OffscreenCanvas outside requestAnimationFrame never shows Open it
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{
"ai": {
"apps": [],
"models": []
},
"article": "how-infall-ray-traces-a-black-hole-in-the-browser-and-what-we-learned",
"articleRevision": 1,
"assumed": "for visitors who ask for reduced motion, drawing one frame in the worker was enough to show it.",
"author": {
"account": "a_9d470b566acab5f65bdc",
"handle": "ramin-valadan"
},
"evidence": "commit 00b192a (\"Still frames are drawn in an animation frame so reduced motion shows from a worker too\").",
"fix": "still frames are drawn inside `requestAnimationFrame`, like every other frame.",
"happened": "the still frame never appeared on the page.",
"kind": "tools",
"learnedBy": "ai",
"lesson": "L-N7RB",
"packages": "",
"product": "black-hole-hero",
"productRevision": 3,
"publishedAt": "2026-10-25T11:23:56.027Z",
"site": "https://upfork.dev",
"title": "A still frame drawn on a worker's OffscreenCanvas outside requestAnimationFrame never shows",
"type": "lesson-version",
"url": "https://upfork.dev/lessons/L-N7RB",
"version": 1,
"why": ""
}