SQL Server System Databases - hankinsoft/SQLPro GitHub Wiki
By default, SQLPro disables system databases for Microsoft SQL Server. They can be restored by running a terminal command. The command you run depends on which version of SQLPro you are using.
SQLPro for MSSQL
defaults write com.hankinsoft.osx.tinysqlstudio ApplicationPreference-DisplayMSSQLSystemDatabases -bool YES
SQLPro Studio
defaults write com.hankinsoft.osx.sqlprostudio ApplicationPreference-DisplayMSSQLSystemDatabases -bool YES
SQLPro Studio (Setapp)
defaults write com.hankinsoft.sqlpro-studio-setapp ApplicationPreference-DisplayMSSQLSystemDatabases -bool YES
You will need to close and re-launch the application to see the system databases.