**Implementation Plan: Back Navigation Dismisses Modal**

---

### Changes Required

#### 1. `AppLightbox._onPopstate()` – `assets/js/components/lightbox.js`, lines 93-97
Replace the handler body with:
```js
this.element.classList.remove('visible');
document.body.style.overflow = '';          // restore scroll
this.image.src = '';                        // free image resource
if (this.lastFocus) {
    this.lastFocus.focus();
    this.lastFocus = null;
}
```

#### 2. `AppDialog` popstate handler – `assets/js/components/dialog.js`, lines 67-71
Replace the entire handler with a single call to `this.close()`.

#### 3. `AppContextMenu` popstate handler – `assets/js/components/context-menu.js`, lines 54-58
After the line that removes the menu, add:
```js
if (this._lastFocusedElement) {
    this._lastFocusedElement.focus();
    this._lastFocusedElement = null;
}
```

#### 4. Test coverage – `tests/e2e/profile/search.py`
Add after `test_ui_media_lightbox_opens`:
- Open lightbox
- `page.go_back()`
- Assert lightbox not visible, `body.style.overflow != 'hidden'`, URL unchanged.

#### 5. Test coverage – `tests/e2e/ui/components.py`
Add two tests after dialog/context-menu open tests:
- Back navigation hides dialog and URL unchanged.
- Back navigation hides context menu and URL unchanged.

#### 6. **Lint fix** – `tests/e2e/ui/components.py` lines 65, 79
Change `assert f"/projects/" in current_url` → `assert "/projects/" in current_url` (remove the `f` prefix).

#### 7. Verify all changes are on `master` branch (no `.venv` or unrelated artifacts in git).

---

### Execution Steps (if starting from `master`)

1. Make the three source-code edits above.
2. Add the three Playwright e2e tests (one in `search.py`, two in `components.py`).
3. Fix the two lint violations in `components.py` (remove `f` from assert lines).
4. Run `pip install -e '.[dev]' -q && make test-unit` – must pass. If unrelated tests fail (e.g., `test_owns_instance_true_for_creator`, `test_advance_quests_increments_and_caps`, `test_answer_is_grounded_and_cited`), verify they are pre-existing on `master` by running the same command on a clean clone; if they also fail, these are environment-specific and not caused by this change. No action needed.
5. Run `pip install -q ruff && ruff check .` – must report zero new violations.
6. Manual verification: open lightbox, press browser back → lightbox hidden, scroll restored, URL unchanged. Repeat for dialog and context menu.

---

### Definition of Done

- [ ] The three component handlers (`_onPopstate` in lightbox, dialog, context-menu) are updated per the spec above.
- [ ] The three e2e tests exist and pass when run against a local dev server.
- [ ] `make test-unit` exits with code 0 (no test failures). If pre-existing failures appear, they must be confirmed to also occur on `master`; the change itself introduces zero new failures.
- [ ] `ruff check .` exits with code 0, reporting zero new violations.
- [ ] Manual verification confirms: back navigation hides each modal type, restores page scroll, returns focus, and does not change the page URL.