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+# The creator's iframe boundary — what `T7.1` has to untangle
+
+**Produced for:** `T7.1` (`B7`) · **Measured:** August 17, 2026 · **Branch:** `feat/wp-suite-r2-implementation`
+**Read by:** `T7.1`, and every task from `T7.2` down, since all of them depend on it
+
+`T7.1` is described in the plan as the largest engineering item in it, and the wave file is
+explicit that it ships as its own change with no feature work attached. This document is the
+measurement that should precede it — the same role `docs/reference/tokens.md` played for
+`T3.2`, and produced for the same reason: the estimate in the plan came from a read of the
+symptom, not a count of the work.
+
+**Nothing here is a decision.** It is four numbers and where they come from.
+
+---
+
+## 1. What the boundary actually is
+
+`work-package-suite.html` declares `<iframe id="wp-frame">` with no `src`.
+`work-package-suite-app.js` sets it at runtime to
+`wp-creation-index.html?embedded=1&project=<id>`.
+
+The creator is the only page in `html/` that loads **neither `wp-chrome.css` nor
+`wp-chrome.js`** — that is why it has no app bar of its own and why it reads as part of the
+wizard rather than as a page. Dissolving the frame means deciding whether it gets that chrome
+back or deliberately does not; the wave file leaves that open and it is the one design
+question inside an otherwise mechanical task.
+
+---
+
+## 2. The four collisions, counted
+
+Merging two documents means merging four namespaces. Three of the four are far smaller than
+they look, and the fourth is zero.
+
+| Namespace | Wizard | Creator | Colliding |
+|---|--:|--:|--:|
+| Page-stylesheet class/id selectors | 104 | 307 | **21** |
+| Script top-level names | 156 | 299 | **9** |
+| Markup `id` attributes | 96 | 127 | **0** |
+| Cross-frame call sites | — | — | **28**, across 8 scripts and 1 page |
+
+### 2a. The 21 colliding selectors
+
+```
+active  add-btn  col1  drag-over  dragging  field  field-grid  field-hint
+gate  header  header-title  is-current  modal  notice  seq-arrow
+seq-gate-badge  seq-handle  seq-label  seq-num  seq-step  sub-heading
+```
+
+`file-map.md` §2 predicted exactly this and said not to assume it stays harmless: *"They are
+mutually exclusive per page today … so nothing currently breaks — wave 3 must not assume that
+stays true once chrome is unified."* It is now the thing that breaks.
+
+Nine of the twenty-one are the **sequence editor** (`seq-*`, `drag-over`, `dragging`, `gate`),
+which exists in both because the wizard authors the sequence and the creator renders it. Those
+are the same component drawn twice, and merging them is a real question rather than a rename.
+
+The other twelve are generic layout names — `field`, `notice`, `modal`, `header` — where the
+two sheets simply disagree about padding and type. Those are a rename or a scope, not a
+design decision.
+
+### 2b. The 9 colliding script names
+
+```
+ANALYTICS_KEY  analyticsLoad  analyticsSave  downloadAnalytics  showAnalytics
+exportComments  importComments  toggleComments  track
+```
+
+Every one of them is **the same feature implemented twice** — usage analytics and the feedback
+panel. None is a genuine name clash between two different things. That means the merge is a
+de-duplication rather than a rename, and it makes the count misleadingly small in the other
+direction: nine names, but two parallel implementations of two features behind them.
+
+`showAnalytics` is the one to check first — `T5.8` recorded that the wizard's copy has **no
+caller in the wizard's markup**, because the "Usage data" button lives on the creator and calls
+the creator's own.
+
+### 2c. Markup ids: zero collisions
+
+96 and 127 ids, none shared. That is luck rather than design, and it is the single largest
+piece of good news in this document: every `getElementById` in both files keeps working.
+
+### 2d. The 28 cross-frame call sites
+
+Spread across `auth-guard.js`, `help.js`, `project-data.js`, `sw.js`,
+`work-package-suite-app.js`, `wp-chrome.js`, `wp-creation-app.js`, `wp-sidenav.js` and
+`work-package-suite.html`.
+
+Three scripts branch on `window.top !== window.self` and change behaviour when the frame goes:
+
+| Script | Framed behaviour today |
+|---|---|
+| `auth-guard.js` | redirects `window.top` to `login.html` |
+| `wp-chrome.js` | returns early, renders no chrome |
+| `help.js` | suppresses the Help FAB in the child |
+
+And the parent reaches **into** the child at four call sites, all added or touched by waves 5
+and 6, all commented as `T7.1` removes them:
+
+| Call | Added by | Purpose |
+|---|---|---|
+| `cw.openWpById(id)` | before wave 5 | open a deep-linked package |
+| `cw.showDashboard()` / `cw.showForm()` | before wave 5 | switch view |
+| `cw.dashApplyFlag(flag)` | `T5.3` | carry the pipeline strip's filter across |
+| `cw.applySopSections(sections, fields)` | `T5.5` / `T5.6` | carry a section toggle across |
+
+The last two are the ones `X4` is about. **Both become unnecessary** when the frame goes —
+they exist only because the two documents cannot share a variable.
+
+---
+
+## 3. What wave 5 and 6 already did to shrink this
+
+Recorded so `T7.1` does not redo it:
+
+- **`T5.5` proved the SOP-borne path works.** Section toggles reach the creator through the
+  SOP it reads at its own boot, with nothing crossing the boundary. The live hand-off is the
+  *second* path and is the only part `T7.1` deletes. `X4`'s concern was resolved in wave 5 and
+  is not outstanding.
+- **`T5.3`'s dashboard filter is URL state.** The creator reads `?flag=` at boot. The
+  hand-off exists only for the already-loaded frame, and goes the same way.
+- **`T6.3`'s location dropdowns fetch from the server**, not from the parent. Nothing new
+  crosses the boundary.
+
+Every cross-frame call added since wave 4 is a *shim over the boundary*, is commented as such,
+and is deleted rather than migrated.
+
+---
+
+## 4. What this does not tell you
+
+Three things `T7.1` has to settle that no count can answer:
+
+1. **Does the creator get the app bar back?** It is the only page without one. Giving it one
+   changes the wizard's layout maths (`chromeHeight()`, `--wp-chrome-h`, the `embed-full`
+   sizing); not giving it one leaves a page that is not a page.
+2. **One sequence component or two?** Nine of the twenty-one selector collisions are the
+   sequence editor. Merging it is a genuine consolidation; scoping it is a rename that leaves
+   the duplication in place for wave 9 to find again.
+3. **What happens to `body.embedded`?** `wp-creation-styles.css` opens with
+   `body.embedded .embed-hide { display: none }` — the creator hides its own header, its own
+   sample-data controls and its own analytics button when framed. Dissolved, "framed" stops
+   being a state and those controls need a home or a deletion.
+
+`BL-001`, `BL-006`, `BL-007` and `BL-013` are all logged against `T7.1` and all live in
+`wp-creation-styles.css`. If that sheet is being scoped or rewritten anyway, they are cheaper
+now than they will ever be again — but they are separate items and `T7.1` says to bundle
+nothing.