Images blurry in Chrome but not Firefox?

Hi —

I’ve really enjoyed the Expound theme but I have a minor issue. I’m not sure if it’s local or across browsers, but some images in my blog look slightly blurry in Chrome compared to Firefox. See this post:

https://www.mountainouswords.com/mountain-air/mount-sherman-to-weston-peak-traverse/

Specifically, the 4th image down (two people on the summit with a dog) looks blurry in Chrome but fine in Firefox (and in the uploaded file).

Any help would be appreciated as this blog is image heavy!