diff --git a/src/app/features/task-view-customizer/task-view-customizer-panel/task-view-customizer-panel.component.html b/src/app/features/task-view-customizer/task-view-customizer-panel/task-view-customizer-panel.component.html
index f7d8f651b7..83e670f976 100644
--- a/src/app/features/task-view-customizer/task-view-customizer-panel/task-view-customizer-panel.component.html
+++ b/src/app/features/task-view-customizer/task-view-customizer-panel/task-view-customizer-panel.component.html
@@ -99,7 +99,7 @@
 
 <!-- Group submenu -->
 <mat-menu #groupMenu="matMenu">
-  @for (opt of OPTIONS.group.list; track opt.type) {
+  @for (opt of customizerService.availableGroupOptions(); track opt.type) {
     <button
       mat-menu-item
       (click)="customizerService.setGroup(opt)"
diff --git a/src/app/features/task-view-customizer/task-view-customizer.service.spec.ts b/src/app/features/task-view-customizer/task-view-customizer.service.spec.ts
index b6f9988e81..02c80d408a 100644
--- a/src/app/features/task-view-customizer/task-view-customizer.service.spec.ts
+++ b/src/app/features/task-view-customizer/task-view-customizer.service.spec.ts
@@ -9,6 +9,7 @@ import { selectAllTags } from '../tag/store/tag.reducer';
 import { getTomorrow } from '../../util/get-tomorrow';
 import { getDbDateStr } from '../../util/get-db-date-str';
 import { BehaviorSubject, Observable, of } from 'rxjs';
+import { map } from 'rxjs/operators';
 import { WorkContextType } from '../work-context/work-context.model';
 import { WorkContextService } from '../work-context/work-context.service';
 import { selectAllTasksWithSubTasks } from '../tasks/store/task.selectors';
@@ -41,6 +42,7 @@ describe('TaskViewCustomizerService', () => {
       activeId: string;
       activeType: WorkContextType;
     }>;
+    isActiveWorkContextProject$: Observable<boolean>;
     mainListTasks$: Observable<TaskWithSubTasks[]>;
     undoneTasks$: Observable<TaskWithSubTasks[]>;
   };
@@ -133,6 +135,7 @@ describe('TaskViewCustomizerService', () => {
         activeId: 'TODAY',
         activeType: WorkContextType.TAG,
       }),
+      isActiveWorkContextProject$: of(false),
       mainListTasks$: of<TaskWithSubTasks[]>([]),
       undoneTasks$: of<TaskWithSubTasks[]>([]),
     };
@@ -1035,6 +1038,9 @@ describe('TaskViewCustomizerService', () => {
               activeWorkContextId: null,
               activeWorkContextType: null,
               activeWorkContextTypeAndId$: ctx$,
+              isActiveWorkContextProject$: ctx$.pipe(
+                map(({ activeType }) => activeType === WorkContextType.PROJECT),
+              ),
               mainListTasks$: of<TaskWithSubTasks[]>([]),
               undoneTasks$: of<TaskWithSubTasks[]>([]),
             },
@@ -1148,12 +1154,12 @@ describe('TaskViewCustomizerService', () => {
     });
   });
 
-  describe('customizeUndoneTasks with group by project (issue #7050)', () => {
-    const inboxTask: TaskWithSubTasks = {
-      id: 'inbox-task',
-      title: 'Inbox Task',
-      tagIds: [],
-      projectId: 'INBOX_PROJECT',
+  describe('customizeUndoneTasks respects current work context (issue #7279)', () => {
+    const projectATask: TaskWithSubTasks = {
+      id: 'project-a-task',
+      title: 'Project A Task',
+      tagIds: ['Tag A'],
+      projectId: 'Project A',
       timeEstimate: 0,
       timeSpentOnDay: {},
       created: 1,
@@ -1164,11 +1170,11 @@ describe('TaskViewCustomizerService', () => {
       attachments: [],
     } as TaskWithSubTasks;
 
-    const projectATask: TaskWithSubTasks = {
-      id: 'project-a-task',
-      title: 'Project A Task',
-      tagIds: [],
-      projectId: 'Project A',
+    const projectBTask: TaskWithSubTasks = {
+      id: 'project-b-task',
+      title: 'Project B Task',
+      tagIds: ['Tag B'],
+      projectId: 'Project B',
       timeEstimate: 0,
       timeSpentOnDay: {},
       created: 2,
@@ -1179,23 +1185,7 @@ describe('TaskViewCustomizerService', () => {
       attachments: [],
     } as TaskWithSubTasks;
 
-    const projectBTask: TaskWithSubTasks = {
-      id: 'project-b-task',
-      title: 'Project B Task',
-      tagIds: [],
-      projectId: 'Project B',
-      timeEstimate: 0,
-      timeSpentOnDay: {},
-      created: 3,
-      subTasks: [],
-      subTaskIds: [],
-      timeSpent: 0,
-      isDone: false,
-      attachments: [],
-    } as TaskWithSubTasks;
-
     const allProjects: Project[] = [
-      { id: 'INBOX_PROJECT', title: 'Inbox', backlogTaskIds: [] } as unknown as Project,
       { id: 'Project A', title: 'Project A', backlogTaskIds: [] } as unknown as Project,
       { id: 'Project B', title: 'Project B', backlogTaskIds: [] } as unknown as Project,
     ];
@@ -1211,14 +1201,15 @@ describe('TaskViewCustomizerService', () => {
       });
 
       mockWorkContextService = {
-        activeWorkContextId: 'INBOX_PROJECT',
+        activeWorkContextId: 'Project A',
         activeWorkContextType: WorkContextType.PROJECT,
         activeWorkContextTypeAndId$: of({
-          activeId: 'INBOX_PROJECT',
+          activeId: 'Project A',
           activeType: WorkContextType.PROJECT,
         }),
-        mainListTasks$: of<TaskWithSubTasks[]>([inboxTask]),
-        undoneTasks$: of<TaskWithSubTasks[]>([inboxTask]),
+        isActiveWorkContextProject$: of(true),
+        mainListTasks$: of<TaskWithSubTasks[]>([projectATask]),
+        undoneTasks$: of<TaskWithSubTasks[]>([projectATask]),
       };
 
       TestBed.configureTestingModule({
@@ -1242,7 +1233,7 @@ describe('TaskViewCustomizerService', () => {
               { selector: selectAllTags, value: mockTags },
               {
                 selector: selectAllTasksWithSubTasks,
-                value: [inboxTask, projectATask, projectBTask],
+                value: [projectATask, projectBTask],
               },
             ],
           }),
@@ -1253,30 +1244,46 @@ describe('TaskViewCustomizerService', () => {
       (testService as any)._allTags = mockTags;
     });
 
-    it('should show tasks from ALL projects when group by project is selected, not just current context', (done) => {
-      // Simulate being on Inbox — undoneTasks$ only has the inbox task
-      const contextUndoneTasks$ = of<TaskWithSubTasks[]>([inboxTask]);
+    it('should only group tasks from the current project when group by tag is selected', (done) => {
+      // User is in Project A — undoneTasks$ only has Project A's task
+      const contextUndoneTasks$ = of<TaskWithSubTasks[]>([projectATask]);
 
-      // Set group to project
-      testService.setGroup({ type: GROUP_OPTION_TYPE.project, label: 'Project' });
+      testService.setGroup({ type: GROUP_OPTION_TYPE.tag, label: 'Tag' });
+
+      const result$ = TestBed.runInInjectionContext(() =>
+        testService.customizeUndoneTasks(contextUndoneTasks$),
+      );
+
+      requestAnimationFrame(() => {
+        result$.subscribe((result) => {
+          expect(result.grouped).toBeDefined();
+          // Project B's task must NOT leak into the view
+          expect(result.list.map((t) => t.id)).toEqual(['project-a-task']);
+          expect(Object.keys(result.grouped!)).toEqual(['Tag A']);
+          expect(result.grouped!['Tag A']?.length).toBe(1);
+          expect(result.grouped!['Tag A']?.[0].id).toBe('project-a-task');
+          done();
+        });
+      });
+    });
+
+    it('should only group tasks from the current project when group by project is selected', (done) => {
+      // Edge case: even though the panel hides this option in a project context,
+      // the service must still scope to the current context if it's set.
+      const contextUndoneTasks$ = of<TaskWithSubTasks[]>([projectATask]);
+
+      testService.setGroup({ type: GROUP_OPTION_TYPE.project, label: 'Project' });
 
-      // customizeUndoneTasks uses toObservable which requires injection context
       const result$ = TestBed.runInInjectionContext(() =>
         testService.customizeUndoneTasks(contextUndoneTasks$),
       );
 
-      // Use requestAnimationFrame since customizeUndoneTasks uses animationFrameScheduler
       requestAnimationFrame(() => {
         result$.subscribe((result) => {
           expect(result.grouped).toBeDefined();
           const groupKeys = Object.keys(result.grouped!);
-          // Should contain tasks from ALL projects, not just Inbox
-          expect(groupKeys).toContain('Inbox');
-          expect(groupKeys).toContain('Project A');
-          expect(groupKeys).toContain('Project B');
-          expect(result.grouped!['Inbox']?.length).toBe(1);
-          expect(result.grouped!['Project A']?.length).toBe(1);
-          expect(result.grouped!['Project B']?.length).toBe(1);
+          expect(groupKeys).toEqual(['Project A']);
+          expect(groupKeys).not.toContain('Project B');
           done();
         });
       });
diff --git a/src/app/features/task-view-customizer/task-view-customizer.service.ts b/src/app/features/task-view-customizer/task-view-customizer.service.ts
index 669e71e3cf..debfde5c01 100644
--- a/src/app/features/task-view-customizer/task-view-customizer.service.ts
+++ b/src/app/features/task-view-customizer/task-view-customizer.service.ts
@@ -1,14 +1,13 @@
 import { Injectable, signal, inject, effect } from '@angular/core';
 import { Observable, animationFrameScheduler, combineLatest } from 'rxjs';
-import { map, observeOn, switchMap, take } from 'rxjs/operators';
+import { map, observeOn, take } from 'rxjs/operators';
 import { TaskWithSubTasks } from '../tasks/task.model';
 import { selectAllProjects } from '../project/store/project.selectors';
-import { selectAllTasksWithSubTasks } from '../tasks/store/task.selectors';
 import { selectAllTags } from './../tag/store/tag.reducer';
 import { Store } from '@ngrx/store';
 import { Project } from '../project/project.model';
 import { Tag } from '../tag/tag.model';
-import { takeUntilDestroyed, toObservable } from '@angular/core/rxjs-interop';
+import { takeUntilDestroyed, toObservable, toSignal } from '@angular/core/rxjs-interop';
 import { computed } from '@angular/core';
 import { getDbDateStr } from '../../util/get-db-date-str';
 import { getWeekRange } from '../../util/get-week-range';
@@ -28,6 +27,7 @@ import {
   FILTER_SCHEDULE,
   SORT_ORDER,
   FILTER_COMMON,
+  OPTIONS,
 } from './types';
 import { DateAdapter } from '@angular/material/core';
 import { lsGetJSON, lsSetJSON } from '../../util/ls-util';
@@ -36,6 +36,10 @@ import { LanguageService } from 'src/app/core/language/language.service';
 import { TranslateService } from '@ngx-translate/core';
 import { T } from '../../t.const';
 
+const GROUP_OPTIONS_NO_PROJECT = OPTIONS.group.list.filter(
+  (opt) => opt.type !== GROUP_OPTION_TYPE.project,
+);
+
 @Injectable({ providedIn: 'root' })
 export class TaskViewCustomizerService {
   private store = inject(Store);
@@ -60,6 +64,16 @@ export class TaskViewCustomizerService {
     ].some((x) => x !== null);
   });
 
+  private _isInProject = toSignal(this._workContextService.isActiveWorkContextProject$, {
+    initialValue: false,
+  });
+
+  // "Group By: Project" would collapse into a single group inside a single-project
+  // view, so offer it only for tag contexts. See issue #7279.
+  availableGroupOptions = computed(() =>
+    this._isInProject() ? GROUP_OPTIONS_NO_PROJECT : OPTIONS.group.list,
+  );
+
   private _stateByContext: Record<string, CustomizerContextState> = lsGetJSON<
     Record<string, CustomizerContextState>
   >(LS.TASK_VIEW_CUSTOMIZER_BY_CONTEXT, {});
@@ -77,7 +91,7 @@ export class TaskViewCustomizerService {
         this._currentContextKey = `${activeType}:${activeId}`;
         const stored = this._stateByContext[this._currentContextKey];
         this.selectedSort.set(stored?.sort ?? DEFAULT_OPTIONS.sort);
-        this.selectedGroup.set(stored?.group ?? DEFAULT_OPTIONS.group);
+        this.selectedGroup.set(this._sanitizeGroupForContext(stored?.group, activeType));
         this.selectedFilter.set(stored?.filter ?? DEFAULT_OPTIONS.filter);
       });
 
@@ -123,24 +137,28 @@ export class TaskViewCustomizerService {
     }
   }
 
+  private _sanitizeGroupForContext(
+    stored: GroupOption | undefined,
+    activeType: WorkContextType,
+  ): GroupOption {
+    if (!stored) return DEFAULT_OPTIONS.group;
+    if (
+      activeType === WorkContextType.PROJECT &&
+      stored.type === GROUP_OPTION_TYPE.project
+    ) {
+      return DEFAULT_OPTIONS.group;
+    }
+    return stored;
+  }
+
   customizeUndoneTasks(undoneTasks$: Observable<TaskWithSubTasks[]>): Observable<{
     list: TaskWithSubTasks[];
     grouped?: Record<string, TaskWithSubTasks[]>;
   }> {
-    const group$ = toObservable(this.selectedGroup);
-    const tasks$ = group$.pipe(
-      switchMap((group) => {
-        const isCrossContext =
-          group.type === GROUP_OPTION_TYPE.project ||
-          group.type === GROUP_OPTION_TYPE.tag;
-        return isCrossContext ? this._allUndoneTasksWithSubTasks$() : undoneTasks$;
-      }),
-    );
-
     return combineLatest([
-      tasks$,
+      undoneTasks$,
       toObservable(this.selectedSort),
-      group$,
+      toObservable(this.selectedGroup),
       toObservable(this.selectedFilter),
     ]).pipe(
       observeOn(animationFrameScheduler),
@@ -171,27 +189,6 @@ export class TaskViewCustomizerService {
     );
   }
 
-  private _allUndoneTasksWithSubTasks$(): Observable<TaskWithSubTasks[]> {
-    return this.store.select(selectAllTasksWithSubTasks).pipe(
-      map((tasks) => {
-        const hiddenProjectIds = new Set(
-          this._allProjects
-            .filter((p) => p.isHiddenFromMenu || p.isArchived)
-            .map((p) => p.id),
-        );
-        const backlogTaskIds = new Set(
-          this._allProjects.flatMap((p) => p.backlogTaskIds || []),
-        );
-        return tasks.filter(
-          (task) =>
-            !task.isDone &&
-            (!task.projectId || !hiddenProjectIds.has(task.projectId)) &&
-            !backlogTaskIds.has(task.id),
-        );
-      }),
-    );
-  }
-
   private applyFilter(
     tasks: TaskWithSubTasks[],
     type: FILTER_OPTION_TYPE | FILTER_COMMON | null,
diff --git a/src/app/features/work-view/work-view.component.spec.ts b/src/app/features/work-view/work-view.component.spec.ts
index 88b1442cbf..e6ba48c6b3 100644
--- a/src/app/features/work-view/work-view.component.spec.ts
+++ b/src/app/features/work-view/work-view.component.spec.ts
@@ -27,26 +27,20 @@ import {
 import { TODAY_TAG } from '../tag/tag.const';
 
 /**
- * Tests for issue #7269: Detail panel closes immediately when opened for a task
- * that only appears in the task-view customizer's list.
- *
- * The WorkViewComponent has a constructor `effect()` that deselects the currently
- * selected task whenever it is no longer present in any of the visible task lists.
- * Previously it only consulted the primary context lists (undone / done / later /
- * overdue / backlog). When the customizer pulls tasks in from other work
- * contexts, the selected task would not be found in any of those lists and would
- * be deselected immediately, closing the detail panel.
- *
- * The fix additionally checks `customizedUndoneTasks().list` before resetting
- * the selection. These tests exercise the real component; the template is
- * overridden to a no-op so we don't have to stand up every child component.
+ * Tests for the constructor effect() in WorkViewComponent that deselects the
+ * currently selected task when it is no longer present in any visible task list
+ * (undone / done / later / overdue / backlog). The customizer's list is
+ * intentionally NOT consulted: after #7279 it is always a subset of the context's
+ * undoneTasks, so checking undoneTasks is sufficient. These tests exercise the
+ * real component; the template is overridden to a no-op so we don't have to
+ * stand up every child component.
  */
 
 const buildTask = (id: string, subTasks: TaskWithSubTasks[] = []): TaskWithSubTasks =>
   ({ id, subTasks }) as unknown as TaskWithSubTasks;
 
 describe('WorkViewComponent', () => {
-  describe('selected task retention effect (#7269)', () => {
+  describe('selected task retention effect', () => {
     let selectedTaskId: ReturnType<typeof signal<string | null>>;
     let setSelectedId: jasmine.Spy;
     let customized$: BehaviorSubject<{ list: TaskWithSubTasks[] }>;
@@ -149,29 +143,8 @@ describe('WorkViewComponent', () => {
       store.overrideSelector(selectTaskRepeatCfgsByTagId, []);
     });
 
-    it('keeps the selection when the task is only in customizedUndoneTasks.list (bug #7269)', async () => {
+    it('deselects when the task is absent from every list', async () => {
       await createComponent();
-      customized$.next({ list: [buildTask('cross-ctx-1')] });
-      selectedTaskId.set('cross-ctx-1');
-      TestBed.flushEffects();
-
-      expect(setSelectedId).not.toHaveBeenCalled();
-    });
-
-    it('keeps the selection when the task is a subtask inside customizedUndoneTasks.list', async () => {
-      await createComponent();
-      customized$.next({
-        list: [buildTask('parent', [buildTask('nested-sub')])],
-      });
-      selectedTaskId.set('nested-sub');
-      TestBed.flushEffects();
-
-      expect(setSelectedId).not.toHaveBeenCalled();
-    });
-
-    it('deselects when the task is absent from every list (including customizedUndoneTasks)', async () => {
-      await createComponent();
-      customized$.next({ list: [buildTask('other')] });
       selectedTaskId.set('ghost');
       TestBed.flushEffects();
 
diff --git a/src/app/features/work-view/work-view.component.ts b/src/app/features/work-view/work-view.component.ts
index 20c6384b26..e7e6505d3a 100644
--- a/src/app/features/work-view/work-view.component.ts
+++ b/src/app/features/work-view/work-view.component.ts
@@ -225,11 +225,6 @@ export class WorkViewComponent implements OnInit, OnDestroy {
       // Check if task is in backlog
       if (this._hasTaskInList(this.backlogTasks(), currentSelectedId)) return;
 
-      // Group/filter may pull tasks from other work contexts into the view;
-      // keep those selected so the detail panel can open for them.
-      if (this._hasTaskInList(this.customizedUndoneTasks()?.list, currentSelectedId))
-        return;
-
       // if task really is gone
       this.taskService.setSelectedId(null);
     });