Not sure if this was happening before but it definitely is with the latest version.
Gallery thunmbail sizes seems to have become smaller with this version. In addition, captions are no longer appearing below thumbnails but rather in a greyed out text when the cursor is hovered over an image in a gallery.
I've tried changing the default thumbnail size but it's not working. As this page shows, some images are showing at the default size and some at the larger size. Even on the larger ones, captions are not showing below the image but on cursor hover.
I'm using the Mantra theme. As the theme is modified, I have a child theme with the modified style sheet. No changes have been made in the customisations to anything dealing with image galleries or captions.