max height for Screenshot / State Snapshot panel

src/mol-plugin-ui/viewport.tsx

@@ -109,7 +109,7 @@ export class ViewportControls extends PluginUIComponent<ViewportControlsProps, V
             </div>
             {this.state.isScreenshotExpanded && <div className='msp-viewport-controls-panel'>
                 <ControlGroup header='Screenshot / State Snapshot' initialExpanded={true} hideExpander={true} hideOffset={true} onHeaderClick={this.toggleScreenshotExpanded}
-                    topRightIcon={Close} noTopMargin>
+                    topRightIcon={Close} noTopMargin childrenClassName='msp-viewport-controls-panel-controls'>
                     <DownloadScreenshotControls close={this.toggleScreenshotExpanded} />
                 </ControlGroup>
             </div>}