For everyone reading this, with the some problem, but on WINDOWS, here what i do:

1. Make a backup of your connections using Tools > Configuration > Backup Connections on Workbench
2. Go to C:\AppData\Roaming\MySQL\Workbench and delete that Workbench folder
3. Uninstall Workbench
4. Install and restore you conections using the same path as step 1