ID 503006 - Opening a project with many clips, and scrolling around in the bin, causes Nuke Studio's memory usage to increase

Problem summary
Opening a project with many clips, and scrolling around in the bin, causes Nuke Studio's memory usage to increase. It does not seem possible to free up this memory again, even after the project is closed.
 
Customer reported version
N/A
 
Customer reported platform
 
Steps to reproduce
 
1) Firstly, clear your cache. The default locations are listed below.

Linux and macOS: /var/tmp/nuke-{uid}/

Windows: C:/Users/{username}/AppData/Local/Temp/nuke/

 
2) Open a .hrox project with many bin items. Some example files are attached. 
NOTE: For the purpose of testing this bug, you should not open any of the clips in the Viewer

3) You should see the RAM usage increase as the project is opened. However, scrolling through the bins in the project may cause the RAM usage to increase further. 

4) Note the current RAM usage, and close the project. 
Attempting to clear cache at this point, by using any of the available options from the Cache menu, doesn't seem to bring the RAM usage down. 

5) Open a different project and repeat steps 2 and 3. Notice that the RAM usage will continue to increase.
 
Expected behaviour
You should be able to free up more RAM after closing a project.
 
Actual behaviour
Opening a project with many clips, and scrolling around in the bin causes Nuke Studio's memory usage to increase. It does not seem possible to free up this memory again, even after the project is closed.
 
Workaround
Unknown.
 
Reproduced by support
This bug has been reproduced in:
Nuke Studio 13.1v2 - Windows 10 - CentOS7 
Nuke Studio 12.0v1 - Windows 10 - CentOS 7
Nuke Studio 9.0v1 - Windows 10
 
Earliest version tested
Nuke Studio 9.0v1
- This issue appears to be in all versions of the product