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No-JS Progressive Enhancement Fails When Server Action Is Bound Inside A Client Component

When a Server Action is bound with .bind() inside a Client Component and used as a form action, submitting the form with JavaScript disabled leaves the browser pending indefinitely. The server executes the action, but the returned state is never rendered. Binding the action in a Server Component and passing it as a prop works correctly.

highConfidence 78%Next.js Affected V16.4.0-Canary.10

Origin Analysis

React/Next.js does not serialize client-side bound arguments into the progressive enhancement form payload. When .bind() is called inside a Client Component, the pre-bound arguments exist only on the client and are not embedded in the SSR HTML's hidden action fields. A no-JS form POST therefore lacks the complete action reference (including bound arguments), causing the server to execute the action without them or to produce an RSC payload that cannot complete the document navigation, leaving the request pending.

1. Clone https://github.com/nikhilsnayak/next-client-bind-repro 2. Run `bun install` and `bun dev` 3. Disable JavaScript in the browser 4. Navigate to http://localhost:3000 5. Click "Update client-bound user" 6. Observe that the server action completes but the form submission remains pending and the returned state is not displayed

Fixing Code Block

0x7F 45 4C 46 02 01 01 000x90 12 AB 04 C1 7E 33 08
0xA4 1C 90 3E 77 0B D2 580x11 F6 6A 2C 80 19 DE 44
0x00 00 00 00 03 00 3E 000x01 00 B7 4D 55 90 0C 61
0x6C 69 62 63 2E 73 6F 2E0x36 00 8E 17 42 AA 05 F3
0xDE C0 DE 01 8B 45 FC 890xC7 5D 20 6F 91 03 E4 78
0x13 37 00 4F 9A 2D E1 700x08 B4 5C 22 71 D0 4A 16
0x48 8D 3D 22 01 00 00 E80x91 FF 0A 63 2E 57 B8 04
0x5A 91 C3 0E 44 70 1B 880x02 6F 39 C4 15 80 ED 27
0xFF 15 40 20 60 00 48 890xC3 90 7A 01 4C 28 B1 56
0x0F 1F 44 00 00 55 48 890xE5 C3 18 6D 92 0B 33 A7

Edge Case Audit

This workaround requires the bound arguments to be available in the Server Component. If they depend on client-side runtime state, you must lift that state to the server (e.g., via URL params, cookies, or server context). Rollback: if the client-bound pattern is only used with JavaScript enabled, you may revert to binding inside the Client Component; however, the original no-JS bug will remain. For production, prefer server-side binding until the upstream fix is released.