You will need to install a user script manager extension to install this script.
Every other kind of image list page on Gelbooru shows the list of tags for an image via the title attribute when you hover on its thumbnail. But not these, because they for some reason use alt for the tags list there instead. No longer.
Hovering over image thumbnails on saves searches pages or wiki entry pages will now show a list of tags, like with search pages et al.
It is unfortunately not practical to do this for "More Like This" thumbnails on image pages, the last remaining thing that does not show tags on hover, due to Gelbooru's current implementation of that feature.