adobe bridge preview of vector files

I'm in Windows 10 64-bit. Adobe Bridge 2020 shows a normal thumbnail for a PSD file and shows a full monitor preview when the spacebar is pressed. However it behaves oddly for Illustrator saved AI files. In a typical Illustrator file (artboard width about 800px or 11 ins), which includes a linked PSD file, I have reduced the artboard to fit a selected object (which is smaller than larger background objects) but the Bridge thumbnail image shows the extent of all the objects outside the artboard even though the visibility is off. So the effect is that the artboard is only a small part of it. I want the artboard to fill the thumbnail image like a PSD thumbnail. Also, when I show the fullscreen preview by pressing the spacebar, the image is the same size as the thumbnail ie it does not fill the monitor screen as the PSD thumbnails do. If I click it to increase to 200% it does expand but the text resolution is very poor.  Can anyone suggest what is going on and how I can change settings to make it work as I want? I may say that exporting, printing etc of the file is unaffected.