AFAIK, its a browser independent change. I'll try put why the previous arrangement is being missed.
Then:
When I browse the forum, top to down, I right click the image I wish to see and click the "Open image in a new tab". Thereafter while it loads (since most of us here in India still suffer from low-bandwidth issues), I browse down the feeds and repeat the same with all the pics I wish to see. While I'm doing this, my images are getting loaded in the new tabs and I can go...
more... to them later.
Now:
Image thumbnails are no longer hyperlinked to the full resolution pictures. So what I have to do is click on the pic, wait for it to load, see it, close it, then go down the feeds, click on the next pic, wait for it to load and so on. Time-consuming and slightly irritating is what I'd frankly call the new arrangement vis-à-vis what we had in place before this.