If you have rooted android phone can easily backup all data of Opera Mini or any Apps.
- You have to install Titanium Backup Pro (Cracked Version).
- Now open this app>select Opera Mini from the lists of Apps>Backup Data. (Prefer SD Card Storage to save this data)
- In future when you go to restore your phone first backup all data and after the restore install all apps and restore all apps data via Titanium Backup Pro apps.