Created attachment 67614 [details] HTML structure of opac-shelves.tt as displayed by Chrome dev tools. The opac-shelves.tt template seems to have mismatch tags, resulting in the opaccredits <div> to be placed inside the main <div>. This can break CSS customization.
Similar issue exists in opac-advsearch.tt.
I don't see a different between opac-shelves.tt, opac-advsearch.tt, and opac-main.tt in the placement of opaccredits. Could you double-check? Do you have any custom HTML (opacheader, opacmain, etc.) which might be causing the HTML to be off?
Created attachment 69422 [details] opac-shelves.tt in Chrome element inspector It might have been my database causing the issue in opac-advsearch.tt, but after clearing all html/css/js from my database, on master branch I could still reproduce the issue for opac-shelves.tt As you can see in the file attached, the comment for closing main is two levels deeper than it should.
Created attachment 69780 [details] Screenshot of correctly-placed OPAC credits on advanced search page
Created attachment 69781 [details] Screenshot of correctly-placed OPAC credits on lists page
I still cannot reproduce this problem.