ISSUE SUMMARY:
When you have "Open Photos and Albums" set to Same Window, if you go to delete a photo, the scroll navigation arrow appears above the delete dialog box. The z-index for the two need to be adjusted.

Hi,

could you please elaborate more? your photo settings using modal box to view the photos, and it looks like this:

Please view the following URL on my live site to see the issue: /community/photos/photo?albumid=1721&photoid=17739

For some reason, my dev site produces an error when I try to change the setting from modal box to open photos in same window.

Hi,

its a bug. but the the temporary fix:

.mfp-wrap {
  z-index: 9999;
}

Hi,

here the official fix:
components/com_community/assets/vendors/magnific-popup/magnific-popup.css
line 115

z-index: 1041;