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OI10 & possibly ribbon control causing form painting issues
Application has the ribbon control on the mdi. The following issue doesn't happen in an application without the ribbon control so we're drawing conclusions.
Here's the visual

Here's the steps
Here's the visual

Here's the steps
- Open any form.
- Open a 2nd form.
- Move the 2nd form so that the bottom of it is out of view (below/behind the taskbar).
- Move the 1st form upwards so that it partially disappears behind the ribbon.
- Move the 2nd form back up into view.
- The bottom of the 2nd form is repainted as the taskbar.