arduino-pro-ide
                                The Arduino IDE for advanced users and developers. Experimental alpha version.
                            
                        How to download and setup arduino-pro-ide
Open terminal and run command
                                            git clone https://github.com/arduino/arduino-pro-ide.git
                                        
                                        git clone is used to create a copy or clone of arduino-pro-ide 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 arduino-pro-ide https://github.com/arduino/arduino-pro-ide/archive/master.zip
Or simply clone arduino-pro-ide with SSH
                                            [email protected]:arduino/arduino-pro-ide.git                                    
                                    If you have some problems with arduino-pro-ide
You may open issue on arduino-pro-ide support forum (system) here: https://github.com/arduino/arduino-pro-ide/issuesSimilar to arduino-pro-ide repositories
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