To open the User-Agent manager, click the button on the bot. User agent is managed by group. You can divide user agents into smaller groups, for example in the figure bellow we can create groups like desktop_chrome, desktop_firefox, desktop_opera, etc instead of just Desktop. It is recommended that you should update your user agent periodically yourself, because over time they will become obsolete!
You can create as many groups as you want, but pay attention to the USAGE RATE column, the total of this column must equals to 100
You can go to developers.whatismybrowser.com or any other sources to get more user agents. For the screen sizes, you may visit screensiz.es
The bot will randomly select a user agent group based on the USAGE RATE you set, then continue to randomly select a setting and user agent string to use.