Cotabby for Windows — double-tap Tab acceptance (test build)

This is a test build for owner validation, not a stable release. It is a
prerelease and does not replace v0.3.0 as the latest stable download.

Source

Commit: 39a300ca8b82e0a42a9d061ae4bcb1b8782079ad (branch codex/upstream-double-tap, draft PR #4)
Ports upstream FuJacob/cotabby #840 double-tap acceptance.
Zip sha256: 02425a7573ed82c1dc7d1de10651c1b1b79f73ea89243ad2ca83e3e59a68a3fc

Opt-in double-tap Tab: Settings → Shortcuts → Accept Entire Suggestion → Double-tap Tab.
The first Tab accepts a word or phrase immediately; a second distinct Tab within 300 ms
accepts the remainder of the same suggestion, once. Repeats stay word-by-word, and moving
the pair is retired by any intervening key, session change, focus change or settings change.
Shift+Tab stays navigation (upstream matches the accept key by keycode plus the whole
modifier set), so a reverse-navigation key press reaches the app instead of being eaten.
Acceptance is serialized and honest. A queued second press is resolved against the live
suggestion instead of being discarded; the 300 ms window is measured from the physical key
events; a word boundary is derived from confirmed insertions rather than a lagging
accessibility read; and an insertion that landed but could not be committed is reported as
such instead of as a refusal.
Failed insertions do not advance or arm the suggestion, the acceptance queue recovers
from a processor fault, and disposal completes every captured key exactly once.
Field identity now uses the UI Automation runtime id, and a field whose provider exposes
none is treated as unproven rather than unowned, so double-tap still works there.

274 portable tests pass; Windows CI run
38570074952 on this exact
commit passed tests, compilation and packaging.
Windows CI also runs the real keyboard hook and UI Automation against WPF fixtures: 9/9 cases
(double tap, held key, unowned Tab, Shift+Tab, cross-process and same-process focus change, held
dispatcher, stale snapshot).
Credential-field privacy proof (real UIA) and native CPU runtime load passed; every packaged byte
is hashed in PACKAGE-MANIFEST.json, and the extracted ZIP was verified member by member.

Published as a prerelease from the branch commit above (draft PR #4), not from main; it does not
replace v0.3.0 as the latest stable download. No merge and no stable tag were performed.
The repository's tag-triggered Release Windows build workflow is intentionally not used for this
test tag: it requires the VERSION file to equal the tag, which a -test tag cannot satisfy. The asset
here is the artifact of the green verification run on this exact commit, byte-verified before upload.

A Tab captured by the accept path whose insertion is then refused is NOT replayed. That key
press is reported, not re-delivered: the app may miss it. This is deliberate; a safe replay path
does not exist yet.
The synthetic hook proof uses a fixture-directed insertion adapter and injected keys. It is not
proof for the production SendInput inserter or for physically held keys.
Live model suggestions, GPU behaviour and real host applications are not verified by
automation and need owner testing.
Global opt-in on the Tab key only: no per-app shortcut overrides, no typing-history collection.
Selecting Double-tap Tab replaces the previous full-accept key choice rather than keeping it dormant.

Extract the complete ZIP into a new folder and keep runtimes\win-x64 beside Cotabby.exe.
Run Cotabby.exe as a standard user (no .NET install needed); your existing settings and model
cache are used.
Settings → Shortcuts → choose Double-tap Tab, then in a normal text field try: one Tab, two
quick Tabs, holding Tab, two slow Tabs, and Shift+Tab.
Check C:\tmp\cotabby-live.log for model load and a constrained decode. Do not share the raw log —
it can contain your typed text.