window structure

1. Tab Counter: Total numbers of tabs in window.
2. Window's title: Editable title of window.
3. Filter:Filter window's tabs
   - Duplicate: Removed duplicate tabs.
   - Domain: Remove all tabs of specific domain name.
4. Sort Tabs: Change order of tabs in window.
   Sort methods:

- Domain ascending
- Domain descending
- Title ascending
- Title descending
- Reverse

5. More Menu: Disply/hide dropdown menu.

6. Suspend:Suspend all tabs in current windows.

7. Merge:Merge current window into selected window.

8. Save:Save current window in database.

9. Delete: Remove current window