Carla instruments - Hard to grab/drag

[zonkmachine]

Bug Summary

It can be hard to grab an open carla instrument in lmms and it feels sometimes 'frozen'.

Steps to reproduce

Open a Carla instrument window and a Triple Oscillator, and move them next to each other on a free space with no other windows. Place the cursor, now a hand icon, above the Triple Oscillator and move it slowly down until it is above the instrument. The hand cursor changes to an arrow and you can now grab the instrument by left clicking it and dragging. Now do the same with the Carla instrument. It will not hand over to the arrow and let you grab it. You can only do this when moving over the top border from another direction.

Affected LMMS versions

stable-1.2 and master

[zonkmachine]

Same issue as #5828