v 12.7.1 - lightbox/thumbnails stopped working

Upgraded last week and the thumbnails as well as lightbox images stopped working.

The images are clickable, but nothing happens.

in console I see:

Lightbox?language=en_GB&docVersion=2.1:6 Uncaught TypeError: Cannot read property 'setStyle' of null
at c.start (Lightbox?language=en_GB&docVersion=2.1:6)
at c.<anonymous> (Lightbox?language=en_GB&docVersion=2.1:6)
at HTMLDocument.<anonymous> (prototype.js:7276)

 

When I click on c.start i see this highlighted:

$(c)})}).defer()},updateImageList:function(){this.updateImageList=Prototype.emptyFunction;document.observe("click",function(a)

{var b=a.findElement("a[rel^\x3dlightbox]")||a.findElement("area[rel^\x3dlightbox]");b&&(a.stop(),this.start(b))}

.bind(this))},start:function(a){$$("select","object","embed").each(function(c)

{c.style.visibility="hidden"}

);var b=this.getPageSize();$("overlay").setStyle({width:b[0]"px",height:b[1]"px"});new Effect.Appear(this.overlay,{duration:this.overlayDuration,from:0,to:LightboxOptions.overlayOpacity});

 

When I click on prototype.js:7276 I get:

Could not load content for http://####mydomain###/xwiki/resources/js/prototype/js/prototype/prototype.js (HTTP error: status code 404, net::ERR_HTTP_RESPONSE_CODE_FAILURE)