gallery-item-title

Hi

I have seen many websites using

<h3 class="gallery-item-title"><a href="https://google.com/">Title</a></h3>

Before the caption so the gallery image gets a nice Title displayed with a link.
I wonder how is this possible cause I can’t get the title to shown.

I read in other posts that by default WP takes the caption text instead of the title so from where is that class=”gallery-item-title”> comming?

You can see an example here of what i mean https://decalaveras.com/