# Development mode

When experimenting with Joplin, for example when [developing a plugin](https://joplinapp.org/api/get_started/plugins/) or trying a theme, you might want to run Joplin in development mode. Doing this will open a second copy of Joplin using a different profile with test notes and notebooks, so you can experiment without risking changing or deleting your data.

To enable Development Mode, go to **Help > Copy dev mode command to clipboard**. This will copy a command to your clipboard. Paste this command in a shell / terminal to run a development version of the app.