click on image message in convo while selection mode, selects message

stylesheets/_session_theme.scss

@@ -80,9 +80,6 @@
     }
   }
 
-  &__container {
-    transition: background-color $session-transition-duration;
-  }
 }
 
 .message {

stylesheets/_theme_dark.scss

@@ -400,7 +400,6 @@
     @include color-svg('../images/timer-00.svg', $color-white-08);
   }
 
-
   // When status indicators are overlaid on top of an image, they use different colors
   .module-expire-timer--with-image-no-caption {
     background-color: $color-dark-05;

ts/components/conversation/Message.tsx

@@ -344,6 +344,7 @@ export class Message extends React.PureComponent<Props, State> {
   // tslint:disable-next-line max-func-body-length cyclomatic-complexity
   public renderAttachment() {
     const {
+      id,
       attachments,
       text,
       collapseMetadata,
@@ -351,6 +352,8 @@ export class Message extends React.PureComponent<Props, State> {
       direction,
       quote,
       onClickAttachment,
+      multiSelectMode,
+      onSelectMessage,
     } = this.props;
     const { imageBroken } = this.state;
 
@@ -391,7 +394,13 @@ export class Message extends React.PureComponent<Props, State> {
             bottomOverlay={!collapseMetadata}
             i18n={window.i18n}
             onError={this.handleImageErrorBound}
-            onClickAttachment={onClickAttachment}
+            onClickAttachment={(attachment: AttachmentType) => {
+              if (multiSelectMode) {
+                onSelectMessage(id);
+              } else if (onClickAttachment) {
+                onClickAttachment(attachment);
+              }
+            }}
           />
         </div>
       );