How to download and setup Sandbox
Open terminal and run command
                                            git clone https://github.com/SandboxPowered/Sandbox.git
                                        
                                        git clone is used to create a copy or clone of Sandbox repositories.
                                        You pass git clone a repository URL. it supports a few different network protocols and corresponding URL formats.
Also you may download zip file with Sandbox https://github.com/SandboxPowered/Sandbox/archive/master.zip
Or simply clone Sandbox with SSH
                                            [email protected]:SandboxPowered/Sandbox.git                                    
                                    If you have some problems with Sandbox
You may open issue on Sandbox support forum (system) here: https://github.com/SandboxPowered/Sandbox/issuesSimilar to Sandbox repositories
Here you may see Sandbox alternatives and analogs
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