diff --git a/specs/coauthoring-inline-editor-diff.md b/specs/coauthoring-inline-editor-diff.md new file mode 100644 index 0000000..bb3f90e --- /dev/null +++ b/specs/coauthoring-inline-editor-diff.md @@ -0,0 +1,437 @@ +--- +status: graduated +--- +# Solution Design: Inline editable proposed-change diff in the Markdown editor (#64) + +| | | +| --- | --- | +| **Author(s)** | Ben Stull (with Claude) | +| **Reviewers / approvers** | Ben Stull | +| **Status** | `graduated` | +| **Version** | v0.1.0 | +| **Source artifacts** | Feature `benstull/vscode-cowriting-plugin#64` (Inline editable proposed-change diff in the Markdown editor + Accept/Reject controls in both surfaces, `type/feature`, `priority/P2`) · Brainstorming session `vscode-cowriting-plugin-0058` (2026-06-26) · Builds on (all shipped): F4 `#12` (propose/accept seam, INV-9/10/11/13), F6 `#17` (baseline / machine-landing), F7 `#21` (rendered preview, pure render engine INV-22), F10 `#29` (interactive review preview — the **clean-editor** decision INV-32; ✓/✗ accept-reject), F11 `#43` (preview toolbar, `data-src` block→source mapping INV-36), document-edit-flow `#42/#47/#46` (block proposals INV-39/40, accept-all INV-42) · Parent specs (graduated): `coauthoring-propose-accept.md`, `coauthoring-diff-view.md`, `coauthoring-rendered-preview.md`, `coauthoring-interactive-review.md`, `coauthoring-document-edit-flow.md` · Lineage: `ben.stull/rfc-app#48` | + +**Change log** + +| Date | Version | Change | By | +| --- | --- | --- | --- | +| 2026-06-26 | v0.1.0 | Initial draft — brainstorming session 0058. Four forks locked with the operator: **(1) editor model** = *optimistic apply + decorations* — on propose, the editor buffer becomes the would-be-accepted text (insertions real & editable & tinted; deletions shown as struck-red non-editable hints); accept = finalize-in-place, reject = revert. **(2) timing** = *on proposal* (turn complete), not a live token-stream into the editor (that stays in #60's notification/OutputChannel). **(3) editor affordance** = CodeLens `Accept ▾ / Reject ▾` above each block, `▾` → QuickPick (this / all); the webview keeps HTML buttons with the same dropdown. **(4) controls parity** = Accept / Reject / Accept-all / Reject-all reachable from **both** the editor and the webview. Two sub-decisions confirmed: a **dedicated `EditorProposalController`** owns optimistic-apply + decorations + CodeLens (keeps `ProposalController` the pure F4 state/seam owner); **saving while pending persists** the proposed (accepted-result) text. Reverses INV-32 and INV-10; supersedes the ✓/✗ glyph controls. | Ben Stull + Claude | + +--- + +## 1. Business Context + +### 1.1 Executive Summary + +Today, when Claude proposes an edit, the change is shown **only in the rendered +review webview** (`oldnew` with ✓/✗ controls); the Markdown +**editor stays deliberately clean** (F10 / INV-32 — "the preview is the single +review surface"). The writer who lives in the editor sees nothing: to review what +Claude proposed they must open the preview panel, and they cannot *edit* the +proposed text in place — they can only accept or reject it wholesale in the +webview. + +This design brings the proposed change **into the Markdown editor itself**: +editable, with a track-changes diff that matches the webview and the post-accept +result **exactly**. It also replaces the per-proposal `✓`/`✗` glyphs with labelled +**Accept** / **Reject** controls — each carrying a `▾` dropdown for **Accept all** +/ **Reject all** — and makes all four actions reachable from **both** the editor +and the webview. The writer can now read, tweak, and resolve a proposal without +leaving the document. + +### 1.2 Background + +The plugin's review model (graduated specs `coauthoring-propose-accept.md`, +`coauthoring-rendered-preview.md`, `coauthoring-interactive-review.md`): + +- A machine edit becomes an **F4 proposal** — a pending-only record + (`Proposal{ id, anchorId, replacement, granularity }` + a `Fingerprint` anchor + whose `text` is the exact target) that **never mutates the document** (INV-10), + re-resolved against the live text at accept (INV-11) and cleared when + accepted/rejected (INV-13). +- The **render engine** (`trackChangesModel.ts`) is a pure, deterministic, + `vscode`-free unit (INV-22): it diffs at **block** granularity (INV-39), word- + merges prose blocks, and emits webview HTML — `renderReview` (annotated) / + `renderPlain` (clean) — with proposal blocks (`proposalBlockHtml`) carrying the + ✓/✗ buttons and `data-src` offsets for selection mapping (INV-36). +- The **F10 decision (INV-32)** removed *all* in-editor decorations + (`grep` confirms zero `TextEditorDecorationType` / `setDecorations` in the tree) + so the webview is the sole review surface; `ProposalController` carries the note + *"no in-editor UI — INV-32 makes the rendered preview the single review surface."* +- The sealed webview is **intent-only** (INV-35): it posts `{accept|reject| + acceptAll|…}` to the host, which routes to `ProposalController.acceptById` / + `rejectById` / `acceptAllProposals` (#46 / INV-42). Accept **applies** the + replacement via the F4 seam (`applyAgentEdit`), which advances the F6 baseline + (machine-landing, INV-18). + +This feature **deliberately reverses two of those decisions** for the editor +surface, and supersedes the ✓/✗ glyph controls in both surfaces. + +### 1.3 Who feels it & why + +The **human coauthor working in the editor** — the writer who asked Claude to edit +and wants to see, adjust, and resolve the result without context-switching to the +preview panel. The pain: the proposed change is invisible in the place they are +actually writing, and it is not editable at all (only accept/reject-able). P2 +(issue #64): it materially deepens the inner-loop "edit-in-place" experience and +unifies the review controls, but the webview review path already works, so it is +an enhancement rather than a gap. + +--- + +## 2. Product Design + +### 2.1 The experience + +When Claude's turn lands a proposal (or, for a document edit, N block proposals), +the **editor** shows the change as track-changes, in place: + +``` + Accept ▾ Reject ▾ ← CodeLens, above each proposed block + The quick ~~brown~~ red fox jumps over the lazy dog. + └ struck red ┘└ green/blue, editable ┘ +``` + +- **Insertions** are **real, editable buffer text**, tinted by origin + (green = human-origin, blue = LLM) — the writer can click in and edit them like + any other text. +- **Deletions** appear as a **struck-red, non-editable hint** rendered adjacent to + the insertion (a decoration, not buffer text) — visually mirroring the webview's + ``. +- The buffer content **is exactly the would-be-accepted result**, so what the + writer sees (and can edit) is precisely what accepting produces. + +Above each proposed block sit two **CodeLens** actions — **`Accept ▾`** and +**`Reject ▾`**. Clicking opens a small QuickPick: + +``` + Accept ▾ → ┌───────────────────────┐ Reject ▾ → ┌───────────────────────┐ + │ Accept this proposal │ │ Reject this proposal │ + │ Accept ALL proposals │ │ Reject ALL proposals │ + └───────────────────────┘ └───────────────────────┘ +``` + +The **webview** shows the same proposal with the same diff, and its controls are +the parallel HTML buttons — **`Accept ▾`** / **`Reject ▾`** — where the `▾` +reveals *Accept all* / *Reject all*. The legacy ✓/✗ glyphs are **replaced** by +these labelled controls in both surfaces. + +All four actions — **Accept**, **Reject**, **Accept all**, **Reject all** — are +reachable from **either** surface and route to the same controller logic +(INV-53). + +### 2.2 Accept / Reject semantics (editable-in-place) + +- **Accept** finalizes the change *that is already in the buffer*: it records the + span's attribution as landed, advances the F6 baseline (machine-landing), and + clears the proposal. It does **not** re-apply text (the text is already there) — + see §3.3. +- **Reject** reverts that block's region back to the stored original + (`Fingerprint.text`), and clears the proposal. +- **If the writer edited the inserted text before deciding:** **Accept** keeps + their edited text (their keystrokes layer on as human authorship over the + proposed span); **Reject** still reverts the whole block to the original. +- **Accept all / Reject all** operate on the current document's pending proposals, + in descending anchor order, skipping orphans (the #46 / INV-42 shape; **Reject + all is new**). + +### 2.3 Save semantics + +Because the proposed text is *in the buffer*, **saving while a proposal is pending +persists the proposed (accepted-result) text** to disk. The deletion hints are +decorations (never buffer text), so the **saved file is clean** — it contains the +accepted-result text, not yet "finalized" only in the sense of attribution / +baseline. "Pending" therefore means *provisional attribution, baseline not yet +advanced* — **not** "document unchanged" (INV-54). We deliberately **allow** the +save rather than block it or strip on save; once the editor shows the live +document, blocking saves would be the surprising behavior. + +### 2.4 What this is *not* (non-goals) + +- **Not live token-streaming into the editor.** The diff appears when the turn + produces a proposal; watching Claude type into the document is out of scope (the + live token stream is #60's notification + OutputChannel). +- **Not a new review *model*.** F4 proposals, anchoring (INV-11), block + granularity (INV-39/40), accept-all (INV-42) are reused; this adds an editor + *surface* and unifies the controls. +- **Not non-Markdown.** Same Markdown-gated scope as the rest of the review UI. +- **Not intra-diagram mermaid editing.** Atomic fences stay atomic (INV-23); a + mermaid block proposal is editable as its whole fence, not sub-diagram. +- **Not removing the webview.** The rendered preview remains a full review surface; + it gains label/dropdown parity, not a demotion. + +### 2.5 Surfaces considered & rejected + +| Editor approach | Why not | +| --- | --- | +| **Read-only decoration overlay** (doc unchanged; ghost insertions via decoration) | The inserted text would **not be editable** — fails the core "human-editable" requirement. | +| **Inline track-changes markup in the buffer** (`{~~old~~|++new++}`) | Pollutes the file on disk with markup until resolved; complex; conflicts with clean save. | +| **Native `vscode.diff` two-pane** | The two-pane diff was *removed* in #34 (F10) precisely to make one review surface; a separate diff editor is not "in the Markdown file." | + +Chosen: **optimistic apply + decorations** — the only model that yields an +editable diff that is *exactly* the accepted result, in the document itself. + +--- + +## 3. Engineering Design + +### 3.1 Architecture + +``` + ┌──────────────────────────────────────────────┐ + one F4 turn ───▶ │ ProposalController (F4 state/seam owner) │ + (#12 propose) │ propose() · finalizeInPlace() · revertInPlace│ + │ · rejectAll() · onDidChangeProposals │ + └───────────────┬──────────────────────────────┘ + │ proposals (pending records + anchors) + ┌─────────────────────┴───────────────────────┐ + ▼ ▼ + ┌───────────────────────────┐ ┌────────────────────────────┐ + │ EditorProposalController │ shared │ TrackChangesPreview- │ + │ (NEW, vscode host) │ pure diff │ Controller (webview) │ + │ · optimistic buffer write │◀──────────────▶ │ · renderReview HTML │ + │ · insertion tint deco │ trackChangesModel│ · Accept▾/Reject▾ buttons │ + │ · deletion-hint deco │ (diff → plan) │ · dropdown → acceptAll/ │ + │ · CodeLens Accept▾/Reject▾│ │ rejectAll │ + └───────────────────────────┘ └────────────────────────────┘ + ▲ ▲ + └──────────── both route actions to ───────────┘ + ProposalController.{finalizeInPlace,revertInPlace, + acceptAll,rejectAll} +``` + +The decisive rule: **one pure diff is the single source of truth** for both +surfaces (INV-49). The editor renders it as *buffer text + decorations + CodeLens*; +the webview renders it as *HTML*. They cannot diverge because they consume the +same hunks. + +### 3.2 Optimistic apply (on propose) — INV-48 + +`propose()` gains a buffer-write step, owned by `EditorProposalController` (so +`ProposalController` stays the pure state owner): + +1. Record the pending proposal(s) + anchor(s) **exactly as today** (the sidecar + record is unchanged: `replacement`, `Fingerprint{text,before,after,lineHint}`, + `granularity`). +2. Write the proposed text into the **live editor buffer**: replace the resolved + anchor span with `replacement` (for a document turn, this makes the buffer + Claude's full proposed document; for a selection turn, the single span). This + write **does not advance the F6 baseline** — the baseline stays at the + pre-proposal text, so the change reads as *pending*, not *landed*. +3. Compute the **decoration plan** from the same per-block word/line diff used by + `acceptBlock` (`wordEditHunks(fp.text, replacement)`): insertion segments → + tinted ranges (buffer coords, offset by the live anchor); deletion segments → + struck-red hint injections (decoration `before`/`after` content) at the segment + boundary. + +Critically, the optimistic write must **not** fire the F4 seam's +`onDidApplyAgentEdit` (which would advance the baseline / register a landed edit). +Optimistic apply is a *distinct* buffer-mutation path from accept; only **accept** +advances the baseline (§3.3). This is the load-bearing distinction that keeps the +change *pending* while *present*. + +### 3.3 Accept = finalize-in-place; Reject = revert-in-place — INV-51 + +Because the proposed text is already in the buffer, the old "accept ⇒ apply via +seam" path would **double-apply**. The accept/reject paths are reworked: + +- **`finalizeInPlace(id)`** — resolve the proposal's anchor against the live text; + record the span's attribution as **landed** (provenance from the proposal's + `author`, word-precise per INV-40 for block granularity); **advance the F6 + baseline** for that region (the machine-landing the seam used to do on apply); + `removeProposal(id)`. No text is re-applied. If the writer edited the inserted + span, the *current* buffer text is what gets finalized (their edits become + layered human authorship). +- **`revertInPlace(id)`** — resolve the proposal's live span; replace it with the + stored original `Fingerprint.text`; `removeProposal(id)`. Reverts the whole + block regardless of any in-place edits. +- **`acceptAll()` / `rejectAll()`** — iterate the current document's pending + proposals in **descending** anchor order (so earlier resolutions don't shift + later offsets), skipping orphans with a tally (INV-42 shape). `acceptAll` reuses + the #46 batch ordering; **`rejectAll` is new** and symmetric. + +Both surfaces (editor CodeLens/QuickPick and webview buttons/dropdown) call these +**same four methods** (INV-53). The webview's existing intent messages are renamed/ +extended (`accept`/`reject`/`acceptAll` + new `rejectAll`) but stay intent-only +(INV-35). + +### 3.4 Single diff source & render-once — INV-49 / INV-50 + +- **INV-49 (single diff source).** The per-proposal diff (block hunks → word/line + edit hunks) is produced by one pure function in `trackChangesModel.ts` (extends + the existing `diffToBlockHunks` / `wordEditHunks`, INV-39/40). The webview HTML + path and the editor decoration-plan path both consume it. Same proposal ⇒ + identical diff in both surfaces (this is the testable parity guarantee). +- **INV-50 (render once).** With optimistic apply, the baseline→buffer delta now + *contains* the proposed change. The renderer must attribute any baseline→buffer + delta that is covered by a **pending proposal** to that proposal (rendered as a + proposal block), and must **not** also render it as an already-landed + machine-diff. Mechanism: the webview render reconciles baseline-diff spans + against pending-proposal anchors; a span covered by a pending proposal is + rendered exactly once, as the proposal. *(This reconciliation is the primary + implementation risk; the implementation plan owns the exact span-mapping, but the + invariant — rendered once — is fixed here.)* + +### 3.5 Editor decorations & CodeLens (the editor surface) + +`EditorProposalController` (new, `vscode` host module) owns: + +- **Two `TextEditorDecorationType`s** — an *insertion tint* (green/blue background, + by provenance) over real buffer ranges, and a *deletion hint* (a + `before`/`after` render-option carrying the struck original text, red, + strikethrough, non-editable). Both are recomputed from the decoration plan on + every `onDidChangeProposals` and on active-editor change. +- **A `CodeLensProvider`** — for each pending proposal whose anchor resolves in the + active document, emit two lenses positioned above the block: `Accept ▾` + (command `cowriting.proposalAcceptMenu` with the proposal id) and `Reject ▾` + (`cowriting.proposalRejectMenu`). Each command opens a `vscode.window + .showQuickPick(["… this proposal","… ALL proposals"])` and dispatches to + `finalizeInPlace`/`acceptAll` or `revertInPlace`/`rejectAll`. +- **Lifecycle wiring** — subscribes to `proposals.onDidChangeProposals` (the same + event the preview uses) and `window.onDidChangeActiveTextEditor`; clears its + decorations + lenses for documents with no pending proposals (so a clean editor + stays clean — INV-32's spirit holds *when there is nothing pending*). + +Deletion hints are **decoration-only** (never buffer text, never saved) and +insertion tints decorate **real** buffer text (INV-52). + +### 3.6 Webview controls (label + dropdown parity) + +`proposalBlockHtml` (`trackChangesModel.ts`) swaps the ✓/✗ glyph buttons for an +**`Accept ▾`** / **`Reject ▾`** control pair. The `▾` opens a small CSS/JS dropdown +in the sealed webview (`preview.ts`/`preview.css`, no network — INV-21) offering +*Accept all* / *Reject all*; selecting posts the corresponding intent +(`acceptAll` / `rejectAll`) or the per-proposal `accept`/`reject`. The host routes +all four to the controller methods of §3.3 (INV-35 preserved). + +### 3.7 Components & files + +| File | Change | +| --- | --- | +| `src/editorProposalController.ts` | **NEW** — optimistic apply, decoration types, deletion-hint injection, `CodeLensProvider`, QuickPick menus; subscribes to `onDidChangeProposals` + active-editor change. | +| `src/proposalController.ts` | Add `finalizeInPlace(id)`, `revertInPlace(id)`, `rejectAll(docKey)`; `propose()` delegates the optimistic buffer write (so the controller stays state-pure); accept/reject routing now finalizes/reverts in place (no seam re-apply). | +| `src/trackChangesModel.ts` | Factor the shared per-proposal diff into one pure producer feeding both surfaces; reconcile pending-proposal spans in `renderReview` (INV-50); swap ✓/✗ → `Accept ▾`/`Reject ▾` in `proposalBlockHtml`. | +| `src/trackChangesPreview.ts` | Route new `rejectAll` intent; keep `accept`/`reject`/`acceptAll`; relabel toolbar/proposal controls. | +| `src/preview.ts` / `preview.css` | Dropdown control for `Accept ▾`/`Reject ▾`; same diff CSS reused. | +| `src/extension.ts` | Register `EditorProposalController`, its CodeLens provider, and the menu commands; wire it alongside `ProposalController`/`TrackChangesPreviewController`. | +| `package.json` | Add `cowriting.rejectAllProposals`, `cowriting.proposalAcceptMenu`, `cowriting.proposalRejectMenu`; CodeLens contribution; markdown-gated `when` clauses. | + +### 3.8 Invariants + +- **INV-48 — Optimistic apply.** On propose, the proposed text is written into the + live editor buffer (the buffer becomes the would-be-accepted result); this write + does **not** advance the F6 baseline and does **not** fire the F4 machine-landing + seam. **Reverses INV-10** (propose no longer leaves the document untouched) and + **INV-32** (the editor is no longer kept unconditionally clean — it shows pending + proposals). +- **INV-49 — Single diff source.** Editor decorations and webview HTML both derive + from one pure, deterministic per-proposal diff (extends `diffToBlockHunks` / + `wordEditHunks`, INV-22/39/40). The same proposal yields the same diff in both + surfaces. +- **INV-50 — Rendered once.** A span covered by a pending proposal is rendered + exactly once — as that proposal — never additionally as an already-landed + baseline diff. +- **INV-51 — Finalize / revert in place.** Accept finalizes the span already in the + buffer (record attribution, advance baseline, clear proposal) without + re-applying text; Reject reverts the block region to the stored + `Fingerprint.text`. No double-apply. +- **INV-52 — Decoration roles.** Deletion hints are decoration-only (non-editable + `before`/`after` content, never buffer text, never saved); insertion tints + decorate real, editable buffer text. +- **INV-53 — Control parity.** Accept / Reject / Accept-all / Reject-all are + reachable from **both** the editor (CodeLens + QuickPick) and the webview + (buttons + dropdown) and route to the same `ProposalController` methods; the ✓/✗ + glyph controls are superseded by labelled `Accept ▾`/`Reject ▾`. +- **INV-54 — Save persists pending.** Saving while a proposal is pending persists + the proposed (accepted-result) text; "pending" denotes provisional attribution / + un-advanced baseline, not document divergence. (Decorations are not persisted, so + the saved file is clean text.) + +### 3.9 Error & edge handling + +- **Orphaned proposal** (anchor no longer resolves) — no editor decorations/lenses + for it; it still surfaces in the webview at end with a dashed border (INV-34); + accept-all/reject-all skip it with a tally (INV-42). +- **Writer edits the inserted span, then accepts** — current buffer text is + finalized (their edits layer as human authorship); **then rejects** — block + reverts to original regardless. +- **External / concurrent edit shifts geometry** — anchors re-resolve on + `onDidChangeProposals` (existing resolve-or-flag); decoration plan + lenses + recompute. +- **Multiple proposals from one turn** — all optimistically applied (buffer = full + proposed document); each block independently finalizable/revertible; descending + order on accept-all/reject-all keeps offsets valid. +- **Reject of an in-buffer span after partial accept of siblings** — each + proposal's revert uses its own live-resolved span, independent of siblings. +- **Non-authorable document** (read-only / not on disk) — controls disabled exactly + as today (`authorable` gating). + +--- + +## 4. Testing & E2E + +Per the §9 pipeline and `coauthoring-*` precedent (this is a VS Code extension — +**no flotilla/PPE**; the gate is unit + host-E2E green). + +- **Unit (the core):** + - The shared per-proposal diff producer: same hunks → insertion/deletion + segments; parity assertion that the decoration plan and the webview HTML derive + identical add/del spans for the same proposal (INV-49). + - `renderReview` render-once reconciliation: a pending-proposal span is emitted + as a proposal block and **not** as a landed baseline diff (INV-50). + - Decoration-plan computation from `wordEditHunks(fp.text, replacement)`: + insertion ranges in buffer coords; deletion-hint positions (INV-52). +- **Host E2E:** + - Propose (via the injectable `editTurn` stub) → editor shows insertion tint + + deletion hint + `Accept ▾`/`Reject ▾` CodeLens; buffer equals the accepted + result (INV-48). + - Edit the inserted text → **finalizeInPlace** keeps the edited text; baseline + advanced; proposal cleared (INV-51). + - **revertInPlace** restores `Fingerprint.text`; proposal cleared. + - Accept / Reject / Accept-all / Reject-all from **both** the editor command path + and the webview intent path produce the same end state (INV-53); `rejectAll` + clears all pending and reverts all blocks. + - Save while a proposal is pending → file on disk has the proposed text; no + decoration markup in the saved bytes (INV-54). + - Webview/editor parity: same proposal renders the same diff in both (INV-49). +- **Manual smoke:** ask Claude to edit a paragraph; confirm the editor diff is + editable, the deletion hint reads correctly, both surfaces' controls resolve it, + and a clean editor returns once nothing is pending. + +--- + +## 5. Delivery Plan (rollout — not a task list) + +One increment, single design-then-build (#64). Ships through branch → PR → `main`; +no migration and no new persisted sidecar shape (the `Proposal` record is +unchanged). The implementation plan (downstream `wgl-planning-and-executing` +session) owns the Task breakdown; a natural cut: + +1. **Shared diff + render-once** — factor the pure per-proposal diff producer; + reconcile pending spans in `renderReview` (INV-49/50) + unit tests. +2. **Accept/reject rework** — `finalizeInPlace` / `revertInPlace` / `rejectAll` on + `ProposalController` (no seam re-apply); unit tests. +3. **Editor surface** — `EditorProposalController`: optimistic apply, decorations, + deletion hints, CodeLens + QuickPick menus; wire in `extension.ts`. +4. **Control parity** — relabel ✓/✗ → `Accept ▾`/`Reject ▾` + dropdown in the + webview; route `rejectAll`; `package.json` commands/`when`. +5. **Host E2E + manual smoke** across both surfaces. + +Reversible by reverting the PR (restores the clean-editor / ✓-✗ webview behavior). + +--- + +## 6. Open Questions + +- **OQ-1 — Provenance tint exactness.** Insertion tint uses green=human-origin / + blue=LLM by the proposal `author`; whether to additionally word-tint *within* a + block by the F3 attribution of edited-in-place text (vs a single block tint) can + follow the existing F9/F10 coloring; v1 tints the proposed insertion by the + proposal author. *(Not blocking.)* +- **OQ-2 (inherited)** — The F11 design (`#43`) remains un-graduated (lives in code + + an issue draft); unrelated to #64 but noted in the shared lineage. Track + separately. +- **OQ-3 — Editor dropdown fidelity.** The editor uses a QuickPick to stand in for + the webview's true `▾` dropdown (CodeLens cannot render a caret menu inline); if + a more button-like affordance is wanted later, a webview-style overlay is a + possible increment. *(Accepted for v1.)*