Only trigger @ keypress on DEV builds.

packages/rich-text/src/component/index.native.js

@@ -896,7 +896,7 @@ export class RichText extends Component {
  onFocus={ this.onFocus }
  onBlur={ this.onBlur }
  onKeyDown={ this.onKeyDown }
- triggerKeyCodes={ [ '@' ] }
+ triggerKeyCodes={ __DEV__ ? [ '@' ] : []}
  onPaste={ this.onPaste }
  activeFormats={ this.getActiveFormatNames( record ) }
  onContentSizeChange={ this.onContentSizeChange }