Another conflict with my Lightbox Gallery plug-in

Hello, I’m using the Lightbox Gallery Pro plugin on my pages on this site:

https://nysbs.org/newsite/

But a new issue has cropped up with the Lightbox Gallery which wasn’t there before.

On every page that contains a gallery, (and there are LOTS of them!) the top menu is flowing over onto a 2nd line, and that isn’t happening on the non-gallery pages.

https://nysbs.org/newsite/tree-swallow-gallery/
https://nysbs.org/newsite/photos/

This is similar, but not exactly, like the other problem I had a while back with the free version of this gallery, described in these threads:

https://www.ads-software.com/support/topic/odd-page-appearance-when-using-gallery-plug-in?replies=9

https://www.ads-software.com/support/topic/odd-behavior-on-page-where-thumbnails-are-displayed?replies=7

I was able to resolve that issue with the information you gave me, and some assistance from the plugin author. I’ve checked the indicated file on the pro version of the gallery, and these lines are not present that I can see.

img {
    max-width: 1600px !important;
}

Is there another bit of code causing the current problem that you can see? This plugin’s author is very hard to communicate with.