MacOS Big Sur - Excel Save As

I've recently updated to MacOS Big Sur and have the following issue with Microsoft Excel.

When opening a new or existing excel document, excel will always open on the first desktop (I use multiple desktops) and not on the currently selected desktop (This has been an issue since the previous OS).

My problem starts here. When excel is moved to another desktop and you want to use "save as" is opens the "save as" window on desktop 1 and then moves between the desktop excel is opened on and desktop one (Flashing between them) untill you press esc.

To actually have a chance to save the document you now have to move excel back to the first desktop and then use the "save as" command.
I updated yesterday to Big Sur 11.2.3 and the problem is still there, even with the latest Excel from Office 2019 (16.47).
Just checked: this only happens when Excel is assigned to a specific desktop. If not, it is possible to move a open file to another desktop and then use 'save as' without any trouble.
MacOS Big Sur - Excel Save As
 
 
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