How to download and setup modmanager
Open terminal and run command
                                            git clone https://github.com/kaniol-lck/modmanager.git
                                        
                                        git clone is used to create a copy or clone of modmanager 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 modmanager https://github.com/kaniol-lck/modmanager/archive/master.zip
Or simply clone modmanager with SSH
                                            [email protected]:kaniol-lck/modmanager.git                                    
                                    If you have some problems with modmanager
You may open issue on modmanager support forum (system) here: https://github.com/kaniol-lck/modmanager/issuesSimilar to modmanager repositories
Here you may see modmanager alternatives and analogs
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