You can't open multiple instances of Station on the same computer: there can only be 1 window with the apps' dock on the left.
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What is possible is to detach any page in a stand-alone window.
This comes useful when:
- you have multiple screens
- you want to open multiple pages side by side.
To open a page as a separate window, just hover on an app's icon and click on the "Detach" button next to the page you want to detach.