Change account gallery in web UI (#10667)

- 3 items per row instead of 2
- Use blurhash for previews
- Animate/hover-to-play GIFs and videos
- Open media modal instead of opening status
- Allow opening status instead with ctrl+click and open in new tab

app/javascript/styles/mastodon/components.scss

@@ -4233,6 +4233,7 @@ a.status-card.compact:hover {
   pointer-events: none;
   opacity: 0.9;
   transition: opacity 0.1s ease;
+  line-height: 18px;
 }
 
 .media-gallery__gifv {
@@ -4762,62 +4763,19 @@ a.status-card.compact:hover {
 
 .account-gallery__container {
   display: flex;
-  justify-content: center;
   flex-wrap: wrap;
-  padding: 2px;
+  justify-content: center;
+  padding: 4px 2px;
 }
 
 .account-gallery__item {
-  flex-grow: 1;
-  width: 50%;
-  overflow: hidden;
+  border: none;
+  box-sizing: border-box;
+  display: block;
   position: relative;
-
-  &::before {
-    content: "";
-    display: block;
-    padding-top: 100%;
-  }
-
-  a {
-    display: block;
-    width: calc(100% - 4px);
-    height: calc(100% - 4px);
-    margin: 2px;
-    top: 0;
-    left: 0;
-    background-color: $base-overlay-background;
-    background-size: cover;
-    background-position: center;
-    position: absolute;
-    color: $darker-text-color;
-    text-decoration: none;
-    border-radius: 4px;
-
-    &:hover,
-    &:active,
-    &:focus {
-      outline: 0;
-      color: $secondary-text-color;
-
-      &::before {
-        content: "";
-        display: block;
-        width: 100%;
-        height: 100%;
-        background: rgba($base-overlay-background, 0.3);
-        border-radius: 4px;
-      }
-    }
-  }
-
-  &__icons {
-    position: absolute;
-    top: 50%;
-    left: 50%;
-    transform: translate(-50%, -50%);
-    font-size: 24px;
-  }
+  border-radius: 4px;
+  overflow: hidden;
+  margin: 2px;
 }
 
 .notification__filter-bar,