Why not get to handle the attribute data-detail?

Trying to adapt this gallery vodkabears.github.io/galereya
Apply it on the page: https://pl-galerie.ru/galerie/
I want to add a new attribute to the picture: data-detail. Value is assigned using PHP. When you view the page's source code shows that the attribute value is not empty, but when you try to display it via js (if you click on the picture to open a large window, a link "read more" at this link in the href attribute must have a value from data-detail). However, undefined is substituted. Same thing when you try to display data-detail just as a string.
In file jquery.galereya.min.js framed line detail:b.getAttribute("data-detail")||"" , but apparently this is not enough. What else do you need?
June 8th 19 at 16:55
1 answer
June 8th 19 at 16:57
There is another function, M=function(a). There need to add ,detail:a.detail||""
In General, for modification it is better not to use minified files, and to do it yourself, after you achieve the desired result.

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