Strange vertical line when launching SDL Trados Studio 2019 SR2

As part of my feedback on SDL Trados Studio 2019 SR2, I have noticed a very strange vertical line appearing as soon as I launch the programme. [Edit: this behaviour does not happen systematically but I haven’t been able to identify precisely when...]

The line disappears as soon as I click in the Editor view.

Just wondering if other users are experiencing this.. It’s only minor but very puzzling.

Note: All my display drivers are up to date.