diff --git a/catalogue/imageviewer.pl b/catalogue/imageviewer.pl
index d78024bde9..9cc96c11d6 100755
--- a/catalogue/imageviewer.pl
+++ b/catalogue/imageviewer.pl
@@ -77,7 +77,7 @@ if ( C4::Context->preference("LocalCoverImages") ) {
     $template->param(
         LocalCoverImages => 1,
         images           => $images,
-        imagenumber      => (@$images ? $images->[0]->imagenumber : undef),
+        imagenumber      => ( $imagenumber || ( @$images ? $images->[0]->imagenumber : undef ) ),
     );
 }
 $template->{VARS}->{'count'}        = $itemcount;
diff --git a/koha-tmpl/intranet-tmpl/prog/en/modules/catalogue/imageviewer.tt b/koha-tmpl/intranet-tmpl/prog/en/modules/catalogue/imageviewer.tt
index b16e906685..5e76e1e3e3 100644
--- a/koha-tmpl/intranet-tmpl/prog/en/modules/catalogue/imageviewer.tt
+++ b/koha-tmpl/intranet-tmpl/prog/en/modules/catalogue/imageviewer.tt
@@ -83,7 +83,7 @@
                     [% FOREACH image IN images %]
                             <li id="imagenumber-[% image.imagenumber | html %]" data-itemnumber="[% image.itemnumber | html %]" data-biblionumber="[% image.biblionumber | html %]" class="thumbnail">
                             <a class="show_cover" data-coverimg="[% image.imagenumber | html %]" href="/cgi-bin/koha/catalogue/imageviewer.pl?biblionumber=[% biblionumber | html %]&amp;imagenumber=[% image.imagenumber | html %]">
-                                [% IF loop.first %]
+                                [% IF image.imagenumber == imagenumber %]
                                     <img class="selected" id="thumbnail_[% image.imagenumber | html %]" src="/cgi-bin/koha/catalogue/image.pl?imagenumber=[% image.imagenumber | html %]&amp;thumbnail=1" alt="Thumbnail" />
                                 [% ELSE %]
                                     <img id="thumbnail_[% image.imagenumber | html %]" src="/cgi-bin/koha/catalogue/image.pl?imagenumber=[% image.imagenumber | html %]&amp;thumbnail=1" alt="Thumbnail" />