Linux Mint 19.3 Xfce - Unity 2019.3.3f1 - Display problem at start

When I start Unity, the console bar at the bottom of the window doesn't display:

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I need to click anywhere in the window, so that the bar comes back into place:

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I reported the error message that pops up at start in another thread; I have no idea if it's related to this display problem.

Edit: it seems that the problem is related to the layouts. Unity loads the last used layout at start, the console bar is hidden outside the bounds of the screen. The same thing happens when I load existing default layouts or custom layouts.

 

All right, the problem disappears if I set my bottom task bar so that it is not automatically hidden...