ID 374348 - The viewport is not updating correctly when navigating Windows 7 only

Problem summary

If there is an object selected from the Objects palette, the viewport is not updating correctly when navigating.

Only a rectangular part of the viewport is updated as expected. 

The issue is occurring occasionally. 

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Customer reported version

4.1v1

Customer reported platform
windows7

Steps to reproduce

1) Open Mari and an example project

2) Set the selection mode to Object

3) Open the Objects palette and select any object 

4) When navigating in the viewport, only rectangular part of the viewport is updated 

Workaround
Pressing anywhere else in the Mari UI resets the viewport.

Reproduced by support

This bug has been reproduced in:

Mari 4.2v1 - Windows 7 

Mari 4.1v1 - Windows 7

Unable to reproduce bug in:
Mari 4.0v1 - Windows 7 - regression

Mari 3.4v3 - Windows 7 

Earliest version tested
4.0v1 - This issue no longer appears in this version and has regressed

Expected behaviour
Viewport to be updated, regardless of the selected objects.

Actual behaviour
Viewport is not updating correctly when there is a selected object