Avatars bleeding over posts at smaller window sizes or when zoomed

Technical Details

Forum version : #phpBB3
Position : Founder
Concerned browser(s) : Mozilla Firefox, Google Chrome
Screenshot of problem : https://i.imgur.com/OKFxGo6.png
Who the problem concerns : All members
When the problem appeared : Always
Forum link : Not entirely necessary, and I guess I'm unreasonably shy

Description of problem

I gave a screenshot of the problem.

I've never seen this on other sites, it's a bit of a problem. I didn't notice it until someone else pointed it out and I replicated it by zooming in two clicks (Ctrl + Scrollbar), and again when I reduced the size of my window.

I'm looking for a way to keep the avatar sizes contained, to size properly with the rest of the forum.

I ran a few different searches to look for this problem but searches just yielded irrelevant topics around avatars.

Edit: I marked Chrome and Firefox, but that's just the two major browsers and the two that I personally tested on before making this post.

Hi, there. If you do need assistance, I would need your forum URL please.

EDIT: Or, you can PM me it if you don't want it to be public.