[Glitch] Add expand/compress image button on image view box

Port 6a2db10f76 to glitch-soc

Signed-off-by: Thibaut Girka <thib@sitedethib.com>

app/javascript/flavours/glitch/styles/components/index.scss

@@ -425,6 +425,20 @@
   align-items: center;
   justify-content: center;
   flex-direction: column;
+  scrollbar-width: none; /* Firefox */
+  -ms-overflow-style: none;  /* IE 10+ */
+
+  * {
+    scrollbar-width: none; /* Firefox */
+    -ms-overflow-style: none;  /* IE 10+ */
+  }
+
+  &::-webkit-scrollbar,
+  *::-webkit-scrollbar {
+    width: 0;
+    height: 0;
+    background: transparent; /* Chrome/Safari/Webkit */
+  }
 
   .image-loader__preview-canvas {
     max-width: $media-modal-media-max-width;

app/javascript/flavours/glitch/styles/components/modal.scss

@@ -40,6 +40,21 @@
   z-index: 9999;
 }
 
+.media-modal__zoom-button {
+  position: absolute;
+  right: 64px;
+  top: 8px;
+  z-index: 100;
+  pointer-events: auto;
+  transition: opacity 0.3s linear;
+  will-change: opacity;
+}
+
+.media-modal__zoom-button--hidden {
+  pointer-events: none;
+  opacity: 0;
+}
+
 .onboarding-modal,
 .error-modal,
 .embed-modal {