Hide lightbox loader after 1s

In case of images with transparency. Either it is loaded at this point or not, the loader has no relation to the image status anyway.

src/js/application.js

@@ -2993,6 +2993,7 @@ function fcn_loadConsentBanner() {
 
 function fcn_showLightbox(target) {
   const lightbox = _$$$('fictioneer-lightbox');
+  const loader = lightbox.querySelector('.loader');
   const lightboxContent = _$('.lightbox__content');
 
   let valid = false;
@@ -3000,6 +3001,7 @@ function fcn_showLightbox(target) {
 
   // Cleanup previous content (if any)
   lightboxContent.innerHTML = '';
+  loader.style.opacity = 1;
 
   // Bookmark source element for later use
   target.classList.add('lightbox-last-trigger');
@@ -3020,6 +3022,10 @@ function fcn_showLightbox(target) {
     lightboxContent.appendChild(img);
     lightbox.classList.add('show');
 
+    setTimeout(() => {
+      loader.style.opacity = 0;
+    }, 1000);
+
     const close = lightbox.querySelector('.lightbox__close');
 
     close?.focus();

src/scss/_lightbox.scss

@@ -45,5 +45,6 @@
     top: 50%;
     left: 50%;
     transform: translate(-50%, -50%);
+    transition: opacity .3s;
   }
 }