ID 9953 - Marquee Selection persists when a project is closed and is invisible after loading the next project

Problem summary
Marquee Selection persists when a project is closed and is invisible after loading the next project

Customer reported version
Mari 6.0v1

Customer reported platform
Multiple

Steps to reproduce
1) Open any project

2) Create a selection with the Marquee Select tool

3) Save and close the project while the selection is still active

4) Open a project (this issue is reproducible whether or not a different project is loaded)

5) Select a Paint node and try to paint

Expected behaviour
The selection should be cleared when the project is closed.

Actual behaviour
The selection persists and is invisible, so paint cannot be applied wherever the invisible selection is present:

Workaround
Unknown.

Reproduced by support
This bug has been reproduced in:
Mari 6.0v1 - Windows 10 - CentOS 7.9
Mari 4.2v1 - Windows 10 - CentOS 7.9

Earliest version tested
Mari 4.2v1 - This issue appears to be in all tested versions of the product