Context

PR #74827 "Implement WebAssembly support detection and fallbacks" was merged. PR #74993 addressed the unsafe delete operations in tests. Several review comments remain unaddressed and are tracked here.

Unaddressed feedback

From @swissspidy

• Remove redundant cross-origin isolation check (feature-detection.ts:55-65) — SharedArrayBuffer requires cross-origin isolation, so without it SharedArrayBuffer would already be undefined and caught by the check at line 47. The cross-origin isolation check will never trigger. Also, the guidance isn't accurate for Chrome which supports Document-Isolation-Policy.

  • Implement WebAssembly support detection and fallbacks #74827 (comment)

• Consider removing WebAssembly check (feature-detection.ts:38-44) — WebAssembly has been supported in all modern browsers for ~9 years; arguably unnecessary.

  • Implement WebAssembly support detection and fallbacks #74827 (comment)

From @andrewserong

• Don't export clearFeatureDetectionCache (upload-media/src/index.ts:13) — Only used in tests, feels like an internal implementation detail that shouldn't be part of the public API.

  • Implement WebAssembly support detection and fallbacks #74827 (comment)

• Move shouldEnableClientSideMediaProcessing to upload-media package (block-editor/src/components/provider/index.js:43-62) — So it can be reused from multiple packages (e.g., the editor package for post locking in Media: Graduate client-side media processing from experimental #75112).

  • Implement WebAssembly support detection and fallbacks #74827 (comment)

• Fix inconsistent trailing periods in reason strings (feature-detection.ts) — Some reason strings end with ., some don't. The console.info appends . Using server-side processing. which causes double .. for reasons that already end with a period.

  • Implement WebAssembly support detection and fallbacks #74827 (comment)

From Copilot

• Add tests for provider gating logic — shouldEnableClientSideMediaProcessing and the fallback path (including the one-time console log) are not tested in provider/test/experimental-provider.js.

Future enhancement (from @andrewserong)

• Low-power device detection — Investigate navigator.hardwareConcurrency, navigator.deviceMemory, and navigator.connection for detecting low-power/low-network devices and gating client-side processing accordingly.
  • Implement WebAssembly support detection and fallbacks #74827 (comment)

Related PRs

• Implement WebAssembly support detection and fallbacks #74827 — Original PR (merged)
• Replace unsafe delete operations in WebAssembly feature detection tests #74993 — Follow-up: Replace unsafe delete operations in tests