Why does my Properties Palette keep slipping down the screen?

[GarryP]

Whenever I open Scribus (1.4.6 on Win 10 64-bit) my PP is always lower down the screen than where I left it. I move it back up and get on with my work then close Scribus. The next time I open Scribus the PP has slipped down the screen again.

The "slippage" isn't much but it's enough to move the "Colour" tab to where it can't be used and it's generally quite annoying. The attached image shows the amount of "slippage"; I usually have the top of the PP at the same level as the top of the window to its left. This has happened since the first day I installed Scribus on my new machine.

This also happened with 1.4.5 on OSX but I thought that was just my system being a bit broken.

Can anyone tell me what's happening please? Does anyone else get this or am I haunted by a ghost in the machine?

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