Hacktoberfest 2026: những issue maintainer đã đánh dấu cho tháng Mười, đang mở và phù hợp người mới. Xem issue Hacktoberfest

Rule proposal: form-prefill-sanitize — extend checkout-checkbox-sanitize to text/email/select prefills

Đang mở
  • Có gì không ổn?
#121 1 bình luận 0 reaction 0 người được giao Xem trên GitHub

Maintainer thường phản hồi trong vòng 3 ngày

Chưa có ai nhận issue này.

Đánh giá

Độ khó
5/5
Thời gian dự kiến
Hơn một tuần
Mức phù hợp với người mới
38/100
Loại issue
Tính năng
Độ rõ ràng
Khá rõ ràng
Mức độ hoạt động
Ít trao đổi
Công nghệ
typescript
Lĩnh vực
frontend, security

Hướng nghiên cứu

Start by reading the existing checkout-checkbox-sanitize and cart-addon-annotate rules and reuse their checkout URL gate. Define the new rule around DOMContentLoaded, the listed control types, hidden-input allowlist and denylist, focus checks, select field restrictions, and host kill-switch; done means covered behavior is tested without touching protected fields or non-checkout forms.

Do mô hình lập chỉ mục viết ra từ nội dung của issue.

Mô tả

enhancement rule-proposal
Category

New defense rule (extension of the checkout-checkbox-sanitize family)

What problem does this solve?

checkout-checkbox-sanitize clears pre-checked checkboxes on checkout pages so the agent doesn't inherit silent opt-ins. The same dark pattern — Mathur et al.'s Preselection — exists for non-checkbox inputs:

  • Pre-populated <select> defaults that pick the costliest shipping speed
  • Pre-filled hidden inputs carrying affiliate / referral / promo IDs that bias pricing or attribution
  • Pre-filled email/phone fields nudging the user toward marketing signup
  • Pre-selected radio defaults on tipping prompts ("18% / 20% / 22% / Custom" with 22% pre-checked)

The agent is then expected to re-select what it actually wants, same contract as the existing checkbox rule.

Proposed solution

On the same checkout-shaped URL gate, walk form controls and:

  • Clear pre-populated <input type="text|email|tel|number"> values when the page state suggests pre-fill (value present without user input — detectable on initial DOM).
  • Reset <select> to its first option (or a blank option if one exists) when the default differs from the natural-first choice.
  • Reset <input type="radio"> groups to unchecked when a default is server-supplied.
  • Clear value on <input type="hidden"> whose name matches a curated affiliate/referral/promo pattern (*aff*, *ref*, *promo*, *utm_*, coupon_id, discount_code) — but only on payment/order pages.

Out of scope for v1: role="textbox" / contenteditable widgets, complex date pickers, anything inside a payment-processor iframe.

Alternatives considered
  • Bundle into checkout-checkbox-sanitize instead of a new rule. Reasonable; the toggle becomes a bigger hammer. Splitting keeps user control finer-grained because text-field clearing has higher FP risk than checkbox clearing.
  • Synthetic blur/change event after clearing. Some sites recalc totals on input events; consider v2 if sites silently re-prefill on input without it.
Controlling false positives
  • Strict URL gate. Payment/order paths only (/cart, /checkout, /basket, /bag, /payment, /order) — never login or arbitrary forms. Reuse the exact gate of cart-addon-annotate and checkout-checkbox-sanitize so the surface is identical to a rule that's already in production.
  • Hard denylist for safety-critical hidden inputs. Never clear <input type="hidden"> whose name matches CSRF/cart/session shapes: _csrf, csrf_token, authenticity_token, cart_id, order_id, session*, nonce, state, _token, anything containing signature. Failure mode here is the form silently rejecting submit, which is worse than the original dark pattern.
  • Allowlist for hidden-input clearing. Only clear hidden inputs whose name matches the affiliate/promo pattern set above. Anything outside the allowlist is preserved.
  • <select>: only reset when the default value is NOT the first option. If the first option is selected (natural default — common pattern is <option value="">Select…</option> or <option>Standard shipping</option> first), the rule does nothing. Avoids clobbering legitimate first-option defaults.
  • Timing. Run on DOMContentLoaded, before browser autofill. Browser autofill that runs after the rule is preserved — meaning the user's password manager and saved addresses still work for inputs the rule has already cleared. Document the ordering explicitly so the contract is clear.
  • Geofencing-aware select defaults. Country/state preselection based on geo is usually legitimate. Mitigation: only reset <select> when the default deviates from the first option AND the field name is in a sneaking-prone set (shipping speed, tip percent, delivery slot, donation amount, insurance plan). Don't touch country/state/region selects.
  • Per-host kill-switch. Loyalty-program checkouts where saved details reappear by design (Amazon 1-Click, Apple Pay flows) can be denylisted by host. These flows are the user's intent.
  • No-op on inputs the user has actually focused. If document.activeElement or :focus-visible matched a field at any point, skip clearing it on rescan.
  • Graceful-failure mode. The worst user-facing outcome is "I need to retype" — recoverable. Document this so a user can clearly attribute the friction to the rule and toggle it off.
Prior art / references
  • Mathur et al. (CSCW 2019), Dark Patterns at Scale. — Preselection category; already cited.
  • Brignull, deceptive.design — Preselection.
  • WHATWG HTML autocomplete attribute spec — informs which fields are legitimate autofill targets vs. server-pushed prefills.
  • Adjacent OSS: Consent-O-Matic sets values to opt out on consent forms — same mechanic, different intent.

Tagged Impact L–M / Complexity M.

Ngôn ngữ chính
TypeScript
Star
34
Fork
3
Merge trung bình
3 ngày 3 giờ
Pull request đã merge (30 ngày)
35

Chuẩn bị môi trường

Bắt đầu từ đâu

  1. Đọc hết issue, rồi đọc hướng dẫn đóng góp của dự án.
  2. Bình luận trên issue rằng bạn sẽ nhận — tránh hai người làm cùng một việc.
  3. Fork repository và làm thay đổi trên một nhánh.
  4. Mở pull request có tham chiếu số hiệu của issue.

Issue khác của pixiebrix/agent-browser-shield

Tất cả issue của pixiebrix/agent-browser-shield

Issue tương tự

Thêm issue về TypeScript

Nhận issue mới trong hộp thư của bạn

Bản tóm tắt ngắn những issue GitHub phù hợp với người mới.