fix #374: open dropdown popups get first claim on pointer routing

Campaign OP gate 2 root cause: UiElement.HitTest walks siblings
front-to-back by z-order, so an OPEN UiMenu's extended button+popup
hit-test union was never consulted when a LATER sibling's rect overlapped
the popup area — on the Config tab every dropdown has rows below it, so
Resolution-item clicks toggled the Full Screen / VSync rows underneath
(the gate session's persisted fullscreen/vsync flips were exactly those
stolen clicks). Latent since UiMenu existed; vendor/chat menus only
worked by z-order luck.

Fix: UiMenu's open/close now registers with UiRoot (SetActivePopup /
ClearActivePopup); a registered popup gets FIRST claim on mouse-down,
scroll, and hover routing; a press outside a live popup dismisses it and
is SWALLOWED (the dismissing click must not act on what sat underneath);
hidden/detached owners self-heal the registration on the next pointer
event. UiMenu gains the IsOpen seam and a single SetOpen writer.

Also in this commit, from the same investigation:
- SilkRuntimeDisplayWindowTarget.Apply documents the fullscreen half
  honestly: IViewProperties.VideoMode is READ-ONLY, so a resolution pick
  while fullscreen cannot switch the display mode through Silk's
  abstract API — split out as #376 (native glfwSetWindowMonitor port)
  rather than half-shipping untested native interop at a gate tail.
- Gate script §OP6 step 8 re-scoped: test resolution in WINDOWED mode.

Regressed by tests/AcDream.App.Tests/UI/UiMenuPopupRoutingTests.cs —
4 tests driving the real UiRoot input path on a mounted overlapping
tree, with an in-test overlap CONTROL click so the popup assertions
cannot pass vacuously (the #372 lesson: only mount+drive-input tests
catch this class; every fixture-conformance test stayed green through
this bug).

Full Release suite: 13,081 passed / 4 skipped / 0 failed.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

docs/ISSUES.md

@@ -24,6 +24,86 @@ What does NOT go here:
 - Every session: scan OPEN issues at start; promote/close anything we touched during the session before ending.
 - Promoting to a Phase: mark as `DONE (promoted to Phase X)` + commit SHA where the Phase entry landed.
 
+## #376 — Fullscreen resolution picks cannot switch the display mode (Silk API limit; needs native glfwSetWindowMonitor)
+
+**Status:** OPEN — filed 2026-08-11, split from #374's investigation.
+While FULLSCREEN, the visible resolution is the display's video mode, and
+Silk's abstract windowing API cannot change it:
+`IViewProperties.VideoMode` is read-only, and Silk fullscreen is
+desktop-mode borderless. `SilkRuntimeDisplayWindowTarget.Apply`
+(`src/AcDream.App/Settings/RuntimeSettingsTargets.cs`) therefore applies a
+Config-tab resolution pick to the WINDOWED size only — visible immediately
+in windowed mode, and on the next return to windowed when picked while
+fullscreen. Retail's own fullscreen switch is a real display-mode change
+(`Device::ForceDisplayResolution`, `gmClient::Init @0x004047af`). Fix
+shape: a native GLFW port — reach the underlying handle and call
+`glfwSetWindowMonitor(window, monitor, 0, 0, width, height, refresh)`
+through `Silk.NET.GLFW` when fullscreen, keeping the abstract path for
+windowed. Needs a physical gate (mode switches can black-screen on bad
+modes; validate against the monitor's mode list first).
+
+## #375 — Configure Keyboard screen renders as a visual mess at the live mount (missing button/tab captions, buttons outside the window, overlapping text)
+
+**Status:** OPEN — filed 2026-08-11 at Campaign OP's second connected gate
+(user report, verbatim observations): "all buttons lacked descriptive
+text", "some buttons were outside of the window", "lacked text in the
+tabs", "text next to the buttons was overlapping. Looked like a mess."
+The screen OPENED (the `[options] gameplay button 0x10000204 clicked`
+log line fired and the user saw the window), so the OP8 mount/wiring is
+alive — the defect family is presentation at the LIVE mount.
+
+**Same false-negative class as #372:** `KeyboardConfigControllerTests`
+runs green against the committed `keyboard_config_21000009.json` fixture,
+so the structural conformance suite cannot see whatever the live
+DAT mount does differently (string resolution, template sizing,
+anchor baselines, window extent). Diagnosis must start from live-mount
+evidence, not the fixture: extend the `ACDREAM_PROBE_LIVE_MOUNT=1` probe
+(`OptionsPanelLiveMountProbeTests` pattern) to mount `0x21000009` against
+the real DATs and dump per-element rect + resolved caption, then compare
+against the user's four observations. Candidate families (to CONFIRM, not
+assume): caption lookups missing their real string table (the exact
+`0x2300000D` class from #372's session), row-template text elements
+sized/positioned from degenerate baselines, and the screen's authored
+extent vs where children actually land.
+
+**Blocks the OP8 connected gate.**
+
+## #374 — Config tab: picking a new Resolution does not resize the window (live gate failure)
+
+**Status:** ROOT-CAUSED + FIXED (this commit) — pending the user's
+re-gate. Filed 2026-08-11 at Campaign OP's second connected gate ("I was
+not able to change the screen resolution").
+
+**ROOT CAUSE — popup hit-test priority, a UiRoot-level routing hole.**
+`UiElement.HitTest` walks siblings front-to-back by z-order; an OPEN
+`UiMenu` extends its hit area beyond its own rect (the button+popup union
+in `UiMenu.OnHitTest`), but any sibling added AFTER the menu whose rect
+overlaps the popup area wins the walk before the menu's extended
+hit-test is ever consulted. On the Config tab every dropdown has rows
+BELOW it — so clicking a Resolution popup item actually clicked the rows
+underneath (the session's persisted `fullscreen: true` + `vsync: false`
+flips were exactly such stolen clicks toggling the Full Screen / VSync
+rows under the open popup). Vendor's and chat's menus only ever worked
+because no overlapping sibling sat in front of them — the hole was
+latent since UiMenu existed. **Fix:** an open popup registers with
+`UiRoot` (`SetActivePopup`) and gets FIRST claim on mouse-down, scroll,
+and hover routing; a press outside the popup dismisses it and is
+SWALLOWED (the standard dropdown-dismiss gesture — the dismissing click
+must not act on whatever sat underneath); hidden/detached owners
+self-heal the registration. Regressed by
+`tests/AcDream.App.Tests/UI/UiMenuPopupRoutingTests.cs` (4 tests, with
+an in-test overlap CONTROL so the assertions cannot pass vacuously).
+
+The investigation also surfaced the fullscreen half — a resolution pick
+while fullscreen cannot switch the display mode through Silk's abstract
+API at all — split out as #376. And the same session's log showed 64
+full `settings.json` disk writes from slider drags (one per drag tick);
+noted here as a minor perf observation, not yet its own issue.
+
+**Re-gate (§OP6 step 8): test the Resolution row in WINDOWED mode** —
+the pick should now register and resize immediately; fullscreen mode
+switching stays #376.
+
 ## #373 — Configure Keyboard: DAT `ActionMap.ConflictingMaps` not consulted — the combat cluster raises false conflict prompts
 
 **Status:** OPEN — filed 2026-08-11 at Campaign OP slice OP8's re-review

docs/research/2026-08-11-campaign-op-test-script.md

@@ -603,8 +603,16 @@ should show no caption.
 ### Live rows — display
 
 8. **Open the Resolution menu (Graphics Options, first row) and pick a
-   different resolution.** The window should resize IMMEDIATELY, live, no
-   restart needed.
+   different resolution — IN WINDOWED MODE.** The window should resize
+   IMMEDIATELY, live, no restart needed. **Gate-2 re-test note (#374):**
+   the first gate's failure here was a client-wide dropdown routing bug —
+   clicks on an open popup's items landed on the rows UNDERNEATH it (your
+   session's Full Screen and VSync flips were those stolen clicks). Fixed;
+   dropdown items now win while a popup is open, and a click outside an
+   open popup dismisses it without acting on what's below. While
+   FULLSCREEN a resolution pick cannot switch the display mode yet
+   (Silk API limit, #376) — it applies on the next return to windowed;
+   do not report that as a step-8 failure.
 9. **Toggle "Full Screen".** The window should switch between windowed and
    fullscreen IMMEDIATELY, live.
 10. **Toggle "Sync To Refresh" (VSync) and drag the "Field of View"