I'm building out a base for our ecommerce team where were sharing and organizing updated product iconography. However, in either a grid or gallery view, the attachments are not showing previews. These are small files (less than 100k) and have tested PNG, SVG and JPG formats with the same result, just a generic image icon.
Clicking into the icon opens a pop-up frame that shows the image against a charcoal background (not great for transparent PNGs) so the files are there and apparently intact - just not showing on a grid or gallery view.
I unfortunately don't have an answer for you, but I am experiencing the same issue. Yesterday, attachments were seeming to attach then disappearing completely. Then later in the day I was able to attach, but the previews were are still not showing (only the icon placeholder). All that to say, I think it may be something wrong on Airtable's end.