Preserve passive canvas geometry while contextual help is open

crates/oa-desktop/src/app.rs

@@ -1383,6 +1383,16 @@ impl App {
                     | Message::SourceSymbolsReady(_)
                     | Message::SourceRenameReady(_)
                     | Message::DiagramUsagesReady(_)
+                    | Message::ScenarioCanvas(
+                        behavior::scenario::CanvasEvent::Scrolled(..)
+                            | behavior::scenario::CanvasEvent::Restored(..)
+                            | behavior::scenario::CanvasEvent::Viewport(..)
+                    )
+                    | Message::TopologyCanvas(
+                        behavior::topology::CanvasEvent::Scrolled(..)
+                            | behavior::topology::CanvasEvent::Viewport(..)
+                    )
+                    | Message::StateDiagram(behavior::state_edit::Event::Viewport(..))
             )
         {
             return Task::none();

crates/oa-desktop/src/app/context_help_tests.rs

@@ -272,3 +272,77 @@ fn context_help_rejects_a_reference_picker_open_queued_from_the_inspector() {
         before
     );
 }
+
+#[test]
+fn context_help_accepts_live_process_viewport_and_rejects_stale_measurements() {
+    use crate::behavior::topology::CanvasEvent;
+    let mut project = Project::empty();
+    let owner = project
+        .add_element(Kind::Process, Layer::Oa, "Response process", None)
+        .unwrap();
+    let mut app = App::with_project(project);
+    send(&mut app, Message::Select(owner));
+    send(&mut app, Message::Page(Page::Behavior));
+    let context = app.topology_context().unwrap();
+    send(
+        &mut app,
+        Message::TopologyCanvas(CanvasEvent::Viewport(context, iced::Size::new(640., 480.))),
+    );
+    let initial = app.behavior.topology.camera_boundary();
+    let before = app.document.snapshot();
+    send(&mut app, Message::Help);
+    assert!(app.context_help);
+    assert_eq!(app.guide.topic, Topic::Chains);
+
+    let resized = iced::Size::new(420., 330.);
+    let context = app.topology_context().unwrap();
+    send(
+        &mut app,
+        Message::TopologyCanvas(CanvasEvent::Viewport(context, resized)),
+    );
+    let measured = app.behavior.topology.camera_boundary();
+    assert!(
+        measured != initial,
+        "Help must admit passive viewport measurements"
+    );
+    assert!(app.context_help);
+    let epoch = app.canvas_epoch;
+    for field in 0..3 {
+        let mut stale = app.topology_context().unwrap();
+        match field {
+            0 => stale.document = Id::new_v4(),
+            1 => stale.owner = Id::new_v4(),
+            _ => stale.revision += 1,
+        }
+        send(
+            &mut app,
+            Message::TopologyCanvas(CanvasEvent::Viewport(stale, iced::Size::new(999., 777.))),
+        );
+        assert!(app.behavior.topology.camera_boundary() == measured);
+        assert_eq!(app.canvas_epoch, epoch);
+    }
+
+    send(&mut app, Message::CloseContextHelp);
+    assert!(!app.context_help);
+    assert!(app.behavior.topology.camera_boundary() == measured);
+    let context = app.topology_context().unwrap();
+    let epoch = app.canvas_epoch;
+    send(
+        &mut app,
+        Message::TopologyCanvas(CanvasEvent::Viewport(context, resized)),
+    );
+    assert_eq!(
+        app.canvas_epoch, epoch,
+        "The size observed behind Help is already current"
+    );
+    let context = app.topology_context().unwrap();
+    send(
+        &mut app,
+        Message::TopologyCanvas(CanvasEvent::Viewport(context, iced::Size::new(700., 500.))),
+    );
+    assert!(app.behavior.topology.camera_boundary() != measured);
+    assert_eq!(app.page, Page::Behavior);
+    assert_eq!(app.selected, owner);
+    assert!(Arc::ptr_eq(&before, &app.document.snapshot()));
+    assert!(!app.document.can_undo());
+}

harness/compact-context-help-20260925.md

@@ -17,6 +17,6 @@ Rejected alternatives: ordinary navigation to the Guide page cleared selection a
 
 ## Verification status
 
-Implementation and six focused state/admission regression tests are prepared. First intermediate `cargo check -p oa-desktop --locked` passed before later overlay and input changes; it is not a check of the final candidate. Current build, focused tests, strict lint, formatting, native comparison and fresh final review remain pending. Baseline captures and raw build logs are local-only until the evidence publication step. No new executable, integrated change, issue closure or release is claimed.
+Implementation and seven focused state/admission regression tests are prepared. The [independent source review](compact-context-help-source-review-20260925.md) records the corrected findings, including passive viewport updates while Help is open. First intermediate `cargo check -p oa-desktop --locked` passed before later overlay and input changes; it is not a check of the final candidate. Current build, focused tests, strict lint, formatting, native comparison and fresh final review remain pending. Baseline captures and raw build logs are local-only until the evidence publication step. No new executable, integrated change, issue closure or release is claimed.
 
 Required native checks: minimum and normal windows; Traceability and Allocation space comparison; multi-selection with long names; Help/F1/Close/Escape with property and behavior drafts; editor focus and canvas scroll/camera restoration; active feedback plus operation failure; State and Process controls; subsequent edit/Undo/Redo and source preservation. Linux remains deferred under the recorded user instruction.

harness/compact-context-help-source-review-20260925.md

@@ -0,0 +1,27 @@
+# Compact contextual help: independent source review
+
+Review date: 2026-09-25. Scope: Gitea issue #39 compact editing chrome and contextual Help, reviewed against base `715036e1` and the issue screenshot. Reviewed source includes `e0812b3932fbb36100516f0981dc9c646eeda56d` plus the subsequent local passive-geometry admission patch and regression test in this change. This is source-review evidence, not native acceptance or executed test evidence.
+
+Criteria: [editing workspace UX review](../docs/ui-review.md), especially preserving pending edits and selection, stable canvas geometry, accessible disclosure, and retaining actionable feedback.
+
+## Findings addressed in source
+
+- The initial Help action used ordinary page navigation, clearing multiselection and selected bends, including before a pending behavior form rejected navigation. Contextual Help now overlays the existing workspace. Close/Escape changes reading state without navigating or applying drafts.
+- App-level modal admission originally ran after allocation and reference-picker fast paths. Help now gates user messages at the beginning of `App::update`; allocation and behavior keyboard ownership are also disabled while Help is open.
+- Combining live gesture feedback with multiselection controls could leave no width for feedback at the configured minimum window size. Selection controls now keep a compact, fixed-height row; current drawing/allocation feedback uses the existing application footer.
+- Footer feedback initially replaced operation status, concealing errors while a promoted edge or drawing tool remained selected. The footer now retains operation status alongside feedback and exposes complete text in its tooltip.
+- Conditional modal wrapping could recreate the editor widget tree. Both closed and open states now use the same outer Stack with the workspace as its first child.
+- State/Process selection guidance removed from persistent chrome was missing from its target Help articles. The States and Chains articles now include group selection, primary-properties semantics and relevant tool/read-only guidance.
+- The new early modal gate initially rejected passive behavior viewport/scroll notifications. It now admits Process/Scenario geometry and State viewport notifications to their existing context-validated handlers, preventing resize observations from being lost while Help is open.
+
+## Regression coverage added
+
+[`context_help_tests.rs`](../crates/oa-desktop/src/app/context_help_tests.rs) covers property drafts and multiselection, source drafts, pending state-transition forms, blocked background actions, contextual Help topic dispatch, Close/Escape, allocation input ownership, queued inspector reference-picker admission, and valid/stale Process viewport measurements during Help and after closing. Assertions include accepted-model snapshot identity and absence of history changes where applicable. Passive geometry intentionally validates document/owner/revision; stale pointer epochs alone do not invalidate measurements.
+
+The reviewer did not compile or execute these tests. Suggested focused command: `cargo test -p oa-desktop context_help_tests`. The integration owner records actual execution and native results separately.
+
+## Scope and remaining verification
+
+Production changes reviewed: desktop App messages/admission, allocation input ownership, Escape bridging, behavior keyboard ownership, architecture/State/Process toolbar layout, guide article disclosure and footer feedback; supporting architecture/UI-review documentation. Regression tests and this record are review artifacts. No model schema, persistence format or authored-model transformation is introduced.
+
+No further concrete source blocker was identified after the fixes above. Native checks remain necessary at 1100×700 and a representative normal size: Help discovery and keyboard reading/dismissal, focus and caret return, preservation of canvas camera/selection and form drafts, resize while Help is open, multiselection control visibility, allocation refusal/destination feedback, current operation failures, and stable canvas bounds through selection/gesture changes. Source inspection and App tests do not establish layout quality, keyboard scrolling, pointer behavior or usability.