ID 284306 - Lag when dragging panels in the UI

Problem summary
When resizing the panels, you'll see the UI update slowly, see attachment.

Customer reported version
Nuke.11.2v3

Customer reported platform
Ubuntu

Steps to reproduce

1) Open Nuke/X/Studio

Reproduced by QA

This bug has been reproduced in:
Nuke11.0v1.000009b on CentOS 7

Expected behaviour
No lag.

Actual behaviour
UI updates slowly.