Steps to reproduce:
When you open a VM viewer, move the mouse to the top, toolbar shows up, you grab it by the left handle (click) and drag it to top, left or right of the window, it allows to be attached to the window. After you attach it, VM viewer window starts resizing/shrinking, and in the end toolbar detaches in most situations (all?).
I'm not sure if this also causes toolbar not to follow the window anymore. (related, or different bug)
Currently I'm running this on gentoo unstable (~amd64), qtcore-5.9.4 and plasma desktop.
Steps to reproduce: When you open a VM viewer, move the mouse to the top, toolbar shows up, you grab it by the left handle (click) and drag it to top, left or right of the window, it allows to be attached to the window. After you attach it, VM viewer window starts resizing/shrinking, and in the end toolbar detaches in most situations (all?).
I'm not sure if this also causes toolbar not to follow the window anymore. (related, or different bug)
Currently I'm running this on gentoo unstable (~amd64), qtcore-5.9.4 and plasma desktop.
Quick edit: I'm running git snapshot from today.