message: Restore copy button icon when sharing permalink
diff: @@ -50,7 +50,8 @@ limitations under the License.
  margin-left: 20px;
  display: inherit;
  }
  -.mx_ShareDialog_matrixto_copy > div {
  +.mx_ShareDialog_matrixto_copy::after {
  + content: "";
  mask-image: url($copy-button-url);
  background-color: $message-action-bar-fg-color;
  margin-left: 5px;
  