Do not display elephant friend in single-column layout (#6222)

app/javascript/mastodon/features/compose/index.js

@@ -94,7 +94,7 @@ export default class Compose extends React.PureComponent {
           <div className='drawer__inner' onFocus={this.onFocus}>
             <NavigationContainer onClose={this.onBlur} />
             <ComposeFormContainer />
-            <div className='mastodon' />
+            {multiColumn && <div className='mastodon' />}
           </div>
 
           <Motion defaultStyle={{ x: -100 }} style={{ x: spring(showSearch ? 0 : -100, { stiffness: 210, damping: 20 }) }}>