This happened 3 times to me this morning.
I see that you’e talking about the size of the pictures. I have a question about this : I selected “infinite canva” and there’s a portion of my work with a greyish background and a portion without anything behind (white). What is this greyish background for ? Is it a layer, and does all my work must be over it ?
The bug (the screen going all grey) happened when I clicked on an image where there is no white background.