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Plan issue-2268: Close Cypress `addListener` crash report (framer-motion v6, unsupported; guarded in current code)

plans/issues/issue-2268.md

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Original Source

Plan issue-2268: Close Cypress addListener crash report (framer-motion v6, unsupported; guarded in current code)

Executor instructions: Follow step by step; run the drift check first. Update the status row for this plan in plans/issues/README.md when done.

Drift check (run first): gh api repos/motiondivision/motion/issues/2268 --jq .state → expect "open". If already closed, mark this plan DONE and stop.

Status

Verdict: INVALID/SUPPORT — close (ancient version + broken test env)

Filed July 2023 against framer-motion 6.5.1 (pinned deliberately for React 16 compat): every Cypress component test rendering a motion.* element throws TypeError: Cannot read properties of undefined (reading 'addListener') at initPrefersReducedMotion. The reporter themselves says "I realize this could be on my end". Zero comments since. Why close:

  • The crash means window.matchMedia("(prefers-reduced-motion)") returned undefined in their Cypress component-test environment — a stubbed/broken matchMedia, since the real browser API always returns a MediaQueryList. That's a test-environment defect, not a library one.
  • Current code (verified at 42bfbe3ed, packages/motion-dom/src/render/utils/reduced-motion/index.ts:3-19) is hardened: const isBrowser = typeof window !== "undefined", an if (window.matchMedia) feature check, and addEventListener("change", ...) instead of v6's addListener.
  • framer-motion v6 is years out of support; per repo policy there is no fix to ship for it and no failing test to write against current code (this repo's own Cypress suite renders motion components in every spec without issue).

Steps

Step 1: Approval gate

Open plans/issues/README.md and find the row for issue-2268. If the row is not marked APPROVED, set this plan's status to BLOCKED in plans/issues/README.md and stop.

Step 2: Comment + close

gh api repos/motiondivision/motion/issues/2268/comments -f body="Closing: this trace means window.matchMedia(...) returned undefined in the Cypress component-test environment (a stubbed/incomplete matchMedia), which a real browser never does — so it's a test-environment issue rather than a library bug. It was also reported against framer-motion 6.5.1, which is long out of support; the reduced-motion init in current versions feature-checks matchMedia and uses addEventListener. If you hit anything similar on motion@12, please open a new issue with a repro."
gh api -X PATCH repos/motiondivision/motion/issues/2268 -f state=closed -f state_reason=not_planned

Verify: gh api repos/motiondivision/motion/issues/2268 --jq .state → "closed".

Done criteria

  • Comment posted; issue closed as not_planned
  • No source files modified
  • plans/issues/README.md status row updated

STOP conditions

  • Recent comments show the same crash on motion@12 — re-check packages/motion-dom/src/render/utils/reduced-motion/index.ts (note: it still assumes matchMedia() returns an object when window.matchMedia exists; a hostile stub returning undefined would still throw — that would then be a small defensive FIX, related to the issue-3735 guard work).