When you create your staging site, some of your plugins will be disabled. You are welcome to re-enable them, but these plugins cause problems on staging sites, and/or perform functions that aren’t necessary on a staging site.
Here is a list of plugins that are currently disabled, and why:
W3 Total Cache, WP Super Cache: Caching plugins are awesome, but aggressive caching can cause some weird problems on staging sites. They can cause weird redirect problems, and caching makes it hard to see the changes you’re making on your staging site. Performance is less of an issue on staging sites: you shouldn’t have much traffic on your staging site.
BackWPup, Backup Buddy: Chances are, you don’t need automatic backups running on your staging site. They use up a lot of resources on the server. You are welcome to re-enable a backup plugin and create backups, but backup plugins are disabled by default on your staging site.