WorkNever-Submit Autofill Engine

Never-Submit Autofill Engine — An MV3 form-fill engine that never submits

never-submit autofill engine · an mv3 form-fill engine that never submits
in progress since 2026 · last touched 2026-06-15

Problem

Long web application forms are slow and repetitive to fill by hand. The obvious automation — a server-side bot that submits on your behalf — gets blocked by modern identity-layer form detection and, worse, takes the human out of the loop on something you want to read before it goes out.

Approach

A Manifest V3 Chrome extension that runs inside your own browser session. Content scripts (reaching into embedded third-party iframes) read the form’s structure; one model call maps each field to your saved profile data; the extension fills the form — and then stops. It never clicks submit; a person always reviews and sends. Because it’s a real human session, bot detection is a non-issue by construction.

Stack

Manifest V3 (content scripts + service worker), a single LLM field-mapping pass, and a data layer kept out of version control. Built by a standing three-agent coding pod — a builder, a profile/asset service, and a separate cross-model reviewer that signs off each milestone.

What shipped

A working extension with the fill engine in place and a never-submit guarantee enforced by a black-box end-to-end suite: it runs against real Chromium with a live submit-suppressor and hard-halts on any submit path (~300+ tests). In active development.

What’s next

Harden field mapping across more form layouts and finish the optional computer-use fallback for the rare non-DOM widgets.

the stack

  • ·Manifest V3
  • ·Chrome Extensions API
  • ·LLM
  • ·h2

Source isn't public yet. The panel can still answer questions about the stack and how it works.