Fix BL-16809 Remove Page sometimes prevented by race condition

PAPERCUTS.md

@@ -19,6 +19,11 @@ House rules:
 
 ---
 
+## 2026-09-04 — Launcher times out waiting for BLOOM_AUTOMATION_READY while a direct dotnet watch works
+- **Cut:** `go.mjs` / `launcherControl.mjs --ensure-running` built Bloom in ~6s, printed `dotnet watch ⌚ Loaded 2 project(s)`, then never saw the ready marker and tore the whole stack down after the 120s `launchTimeoutMs` in `scripts/watchBloomExe.mjs` — three times in a row. Running `dotnet watch run --project src/BloomExe/BloomExe.csproj --non-interactive -- --automation` by hand from the same shell started Bloom and printed `BLOOM_AUTOMATION_READY` within seconds (alongside a running BetaInternal, so it was not the single-instance token).
+- **Idea:** Find what differs when `watchBloomExe.mjs` spawns dotnet watch (`--vite-port`/`--label` args, control-port env, stdout piping) and make the launcher print dotnet watch's later output or the Bloom PID's window titles when it gives up, so the failure is diagnosable. Consider making the timeout configurable.
+- **Context:** worktree Format-Gear-Positioning-356 at the Version6.5 tip, while fixing BL-16809; hit by Claude.
+
 ## 2026-07-30 — Visual regression suite reports only the first stale image per case
 - **Cut:** Each case in `src/BloomVisualRegressionTests/index.spec.ts` compares the book preview
   and then every bloom-player page in sequence, and every comparison throws on failure — so the

src/BloomBrowserUI/bookEdit/TopicChooser/TopicChooserDialog.tsx

@@ -54,10 +54,7 @@ export const TopicChooserDialog: React.FunctionComponent<
 
     const dialogTitle = useL10n("Choose Topic", "TopicChooser.Title");
 
-    // Tell edit tab to disable everything when the dialog is up.
-    // (Without this, the page list is not disabled since the modal
-    // div only exists in the book pane. Once the whole edit tab is inside
-    // one browser, this would not be necessary.)
+    // Tell C# to lock the workspace tabs while the dialog is up.
     React.useEffect(() => {
         if (propsForBloomDialog.open === undefined) return;
 

src/BloomBrowserUI/bookEdit/bloomField/BloomField.ts

@@ -7,7 +7,7 @@ import BloomMessageBoxSupport from "../../utils/bloomMessageBoxSupport";
 import { tryProcessHyperlink } from "./hyperlinks";
 import { EditableDivUtils } from "../js/editableDivUtils";
 import $ from "jquery";
-import { showLinkTargetChooserDialog } from "../../react_components/LinkTargetChooser/LinkTargetChooserDialogLauncher";
+import { getWorkspaceBundleExports } from "../js/workspaceFrames";
 import { getLocalization } from "../../react_components/l10n";
 import { kNoIndentClass } from "../textContextMenu/noIndent";
 
@@ -401,6 +401,9 @@ export default class BloomField {
 
         ckeditor.addCommand("setupHyperlink", {
             exec: function (edt) {
+                // Shown from the workspace root so its backdrop covers the page list too.
+                const showLinkTargetChooserDialog =
+                    getWorkspaceBundleExports().showLinkTargetChooserDialog;
                 showLinkTargetChooserDialog("", (url) => {
                     if (!url) return;
                     get("app/selectedBookInfo", (bookInfo) => {

src/BloomBrowserUI/bookEdit/copyrightAndLicense/CopyrightAndLicenseDialog.tsx

@@ -68,10 +68,7 @@ export const CopyrightAndLicenseDialog: React.FunctionComponent<{
 
     const dialogTitle = useL10n("Copyright and License", "CopyrightAndLicense");
 
-    // Tell edit tab to disable everything when the dialog is up.
-    // (Without this, the page list is not disabled since the modal
-    // div only exists in the book pane. Once the whole edit tab is inside
-    // one browser, this would not be necessary.)
+    // Tell C# to lock the workspace tabs while the dialog is up.
     React.useEffect(() => {
         if (propsForBloomDialog.open === undefined) return;
 

src/BloomBrowserUI/bookEdit/js/linkGrid.ts

@@ -4,7 +4,7 @@ import WebSocketManager, {
     IBloomWebSocketEvent,
 } from "../../utils/WebSocketManager";
 import { postJson } from "../../utils/bloomApi";
-import { showBookGridSetupDialog } from "../../react_components/BookGridSetup/BookGridSetupDialog";
+import { getWorkspaceBundleExports } from "./workspaceFrames";
 import { Link } from "../../react_components/BookGridSetup/BookLinkTypes";
 
 function getLanguage1Tag(): string {
@@ -56,7 +56,8 @@ export function editLinkGrid(linkGrid: HTMLElement) {
             };
         });
 
-    showBookGridSetupDialog(
+    // Shown from the workspace root so its backdrop covers the page list too.
+    getWorkspaceBundleExports().showBookGridSetupDialog(
         currentLinks,
         // callback if they press OK
         (links: Link[]) => {

src/BloomBrowserUI/bookEdit/toolbox/canvas/canvasControlRegistry.ts

@@ -74,7 +74,6 @@ import {
     showDialogToChooseSoundFileAsync,
 } from "../games/GameTool";
 import { showTalkingBookTool } from "../talkingBook/showTalkingBookTool";
-import { showLinkTargetChooserDialog } from "../../../react_components/LinkTargetChooser/LinkTargetChooserDialogLauncher";
 import { kBloomBlue } from "../../../bloomMaterialUITheme";
 import { trackEvent } from "../../../utils/bloomApi";
 import {
@@ -1149,6 +1148,9 @@ export const controlRegistry: Record<TopLevelControlId, IControlDefinition> = {
             // element itself (not on any nested image container).
             const currentUrl =
                 ctx.canvasElement.getAttribute("data-href") ?? "";
+            // Shown from the workspace root so its backdrop covers the page list too.
+            const showLinkTargetChooserDialog =
+                getWorkspaceBundleExports().showLinkTargetChooserDialog;
             showLinkTargetChooserDialog(currentUrl, (newUrl) => {
                 if (newUrl) {
                     ctx.canvasElement.setAttribute("data-href", newUrl);

src/BloomBrowserUI/bookEdit/toolbox/talkingBook/AdjustTimingsDialog.tsx

@@ -115,10 +115,7 @@ export const AdjustTimingsDialog: React.FunctionComponent<{
     );
     const [timingsFilePath, setTimingsFilePath] = useState<string>();
 
-    // Tell edit tab to disable everything when the dialog is up.
-    // (Without this, the page list is not disabled since the modal
-    // div only exists in the book pane. Once the whole edit tab is inside
-    // one browser, this would not be necessary.)
+    // Tell C# to lock the workspace tabs while the dialog is up.
     React.useEffect(() => {
         if (propsForBloomDialog.open === undefined) return;
         postBoolean("editView/setModalState", propsForBloomDialog.open);

src/BloomBrowserUI/bookEdit/workspaceRoot.ts

@@ -8,6 +8,7 @@ import {
     hideColorPickerDialog as doHideColorPickerDialog,
 } from "../react_components/color-picking/colorPickerDialog";
 import { postJson } from "../utils/bloomApi";
+import { Link } from "../react_components/BookGridSetup/BookLinkTypes";
 import "../modified_libraries/jquery-ui/jquery-ui-1.10.3.custom.min.js"; //for dialog()
 import $ from "jquery";
 
@@ -33,6 +34,14 @@ export interface IWorkspaceExports {
     hideColorPickerDialog(): void;
     showCopyrightAndLicenseDialog(imageUrl?: string): void;
     showEditViewTopicChooserDialog(): void;
+    showLinkTargetChooserDialog(
+        currentUrl: string,
+        onSetUrl: (url: string) => void,
+    ): void;
+    showBookGridSetupDialog(
+        currentLinks: Link[],
+        setLinksCallback: (links: Link[]) => void,
+    ): void;
     showAdjustTimingsDialogFromWorkspaceRoot(
         currentTextBox: HTMLElement,
         // The split and applyTimingsFile calls both return a list of new timings,
@@ -70,6 +79,13 @@ import { getEditablePageBundleExports } from "./js/workspaceFrames";
 export { getEditablePageBundleExports };
 import { showPageChooserDialog } from "../pageChooser/PageChooserDialog";
 export { showPageChooserDialog };
+// These two are launched from code that runs in the page iframe. They must be shown from here,
+// the workspace root, so that their modal backdrop covers the whole workspace including the
+// page list; rendered in the page iframe the backdrop covers only the book pane (BL-16809).
+import { showLinkTargetChooserDialog } from "../react_components/LinkTargetChooser/LinkTargetChooserDialogLauncher";
+export { showLinkTargetChooserDialog };
+import { showBookGridSetupDialog } from "../react_components/BookGridSetup/BookGridSetupDialog";
+export { showBookGridSetupDialog };
 
 import "../lib/errorHandler";
 import { showBookSettingsDialog } from "./bookAndPageSettings/BookAndPageSettingsDialog";
@@ -449,6 +465,8 @@ interface WorkspaceBundleApi {
     getToolboxBundleExports: typeof getToolboxBundleExports;
     getEditablePageBundleExports: typeof getEditablePageBundleExports;
     showPageChooserDialog: typeof showPageChooserDialog;
+    showLinkTargetChooserDialog: typeof showLinkTargetChooserDialog;
+    showBookGridSetupDialog: typeof showBookGridSetupDialog;
     showBookSettingsDialog: typeof showBookSettingsDialog;
     showRegistrationDialog: typeof showRegistrationDialogForEditTab;
     showAboutDialog: typeof showAboutDialog;
@@ -495,6 +513,8 @@ window.workspaceBundle = {
     getToolboxBundleExports,
     getEditablePageBundleExports,
     showPageChooserDialog,
+    showLinkTargetChooserDialog,
+    showBookGridSetupDialog,
     showBookSettingsDialog,
     showRegistrationDialog: showRegistrationDialogForEditTab,
     showAboutDialog,

src/BloomBrowserUI/pageChooser/PageChooserDialog.tsx

@@ -124,10 +124,7 @@ export const PageChooserDialog: React.FunctionComponent<
         HTMLDivElement | undefined
     >(undefined);
 
-    // Tell edit tab to disable everything when the dialog is up.
-    // (Without this, the page list is not disabled since the modal
-    // div only exists in the book pane. Once the whole edit tab is inside
-    // one browser, this would not be necessary.)
+    // Tell C# to lock the workspace tabs while the dialog is up.
     useEffect(() => {
         if (open === undefined) return;
 

src/BloomBrowserUI/react_components/LinkTargetChooser/LinkTargetChooserDialogLauncher.tsx

@@ -2,6 +2,9 @@ import * as React from "react";
 import { ShowEditViewDialog } from "../../bookEdit/workspaceRoot";
 import { LinkTargetChooserDialog } from "./LinkTargetChooserDialog";
 
+// Call this only from the workspace root (from the page iframe, go through
+// getWorkspaceBundleExports().showLinkTargetChooserDialog): ShowEditViewDialog renders in the
+// calling frame's document, and only in the root does the dialog's backdrop cover the page list.
 export const showLinkTargetChooserDialog = (
     currentUrl: string,
     onSetUrl: (url: string) => void,

src/BloomBrowserUI/react_components/registration/registrationDialogLauncher.tsx

@@ -38,7 +38,7 @@ export const RegistrationDialogLauncher: React.FunctionComponent<
 
     React.useEffect(() => {
         if (props.dialogEnvironment?.mode === Mode.Edit) {
-            // Tell edit tab to disable everything when the dialog is up
+            // Tell C# to lock the workspace tabs while the dialog is up
             postBoolean("editView/setModalState", propsForBloomDialog.open);
         }
     }, [props.dialogEnvironment?.mode, propsForBloomDialog.open]);

src/BloomExe/Edit/EditingView.cs

@@ -506,7 +506,7 @@ internal void StartNavigationToEditPage(IPage page)
                 _model.SetupServerWithCurrentBookToolboxContents();
                 WorkspaceView.ReloadWorkspaceRootDocument();
             }
-            SetModalState(false); // ensure _pageListView is enabled (BL-9712).
+            SetModalState(false); // ensure the tabs are not left locked (BL-9712).
 #if MEMORYCHECK
             // Check memory for the benefit of developers.
             Bloom.Utils.MemoryManagement.CheckMemory(
@@ -1545,18 +1545,25 @@ public void Dispose()
         public string HelpTopicUrl => "/Tasks/Edit_tasks/Edit_tasks_overview.htm";
 
         /// <summary>
-        /// Prevent navigation, e.g. while a dialog box is showing in the browser control
+        /// Lock workspace navigation (the tabs), e.g. while a dialog box is showing in the browser
+        /// control. Calls nest: each true must be matched by a false.
         /// </summary>
+        /// <remarks>
+        /// This used to disable the page list as well, because the page list lived in its own
+        /// browser and a modal dialog's backdrop in the main browser could not cover it. The whole
+        /// edit tab is in one browser now, so the backdrop already blocks the page list, and the
+        /// C# gate could only do harm: the browser posted the dialog's "closed" notice and the command
+        /// the dialog confirmed (e.g. Remove Page) as two concurrent requests, and when the command was
+        /// handled first it was silently refused (BL-16809).
+        /// </remarks>
         internal void SetModalState(bool isModal)
         {
             if (isModal)
                 _modalDialogDepth++;
             else
                 _modalDialogDepth = Math.Max(0, _modalDialogDepth - 1);
 
-            var isActuallyModal = _modalDialogDepth > 0;
-            _pageListView.Enabled = !isActuallyModal;
-            _workspaceView?.SetTabsEnabled(!isActuallyModal);
+            _workspaceView?.SetTabsEnabled(_modalDialogDepth == 0);
         }
 
         public void ShowAddPageDialog()

src/BloomExe/Edit/PageListController.cs

@@ -105,10 +105,5 @@ public void EmptyThumbnailCache()
         {
             _thumbNailList.EmptyThumbnailCache();
         }
-
-        public bool Enabled
-        {
-            set { _thumbNailList.Enabled = value; }
-        }
     }
 }

src/BloomExe/Edit/PageThumbnailList.cs

@@ -203,8 +203,7 @@ private List<IPage> UpdateItemsInternal(IEnumerable<IPage> pages)
 
         internal void PageClicked(IPage page)
         {
-            if (Enabled)
-                InvokePageSelectedChanged(page);
+            InvokePageSelectedChanged(page);
         }
 
         /// <summary>
@@ -217,7 +216,7 @@ internal void PageClicked(IPage page)
         /// </remarks>
         internal bool IsContextMenuCommandEnabled(IPage page, string commandId)
         {
-            if (!Enabled || page == null)
+            if (page == null)
                 return false;
 
             switch (commandId)
@@ -272,7 +271,6 @@ internal void ExecuteContextMenuCommand(IPage page, string commandId)
         }
 
         private PageListApi _pageListApi;
-        internal bool Enabled = true;
 
         // This gets invoked by Javascript (via the PageListApi) when it determines that a particular page has been moved.
         // newIndex is the (zero-based) index that the page is moving to