Can't switch tool window state from 'Floating' to 'Dockable'

Can't switch tool window state from 'Floating' to 'Dockable' using the toolwindow header drop down menu.
Steps to reproduce:
1. Create simple win-form app and put dockManager on the main form
2. Create two tool windows, run the app
3. Right-click on the header of one of tool window, select 'Floating' from drop-down menu
4. Observe tool window state switched to floating
5. Right-click on the header of floating tool window and select 'Dockable'
6. Observe the window state remains unchanged

This is reproducible using uistudio 2.0.96 as well as on 2.0.112.
Note: double click works well to switch the state

Please provide quick workaround if possible.
Regards.