Thumbnails aspect ratio is changed depends on Browser

Hi, we’re facing a recently popped issue: Thumbnails aspect racio is changed when we display assets in thumbnail view like the attatched images.
When we tested on Vivaldi, the display reciao is 1:1 sqaure, which is the same as results before a few days/months back. Which was same on Chrome as well.
But when we see the same page on Chrome now, the thumbnail display racio is cahnged only by hight long aspect racio images.

Why is this happing? Is this only local issues for our environment?

On Chrome:

On Vivaldi:

It looks bug… but is it a new feature for supported browsers?
Sqaure display is much prefrered feature, I believe.