

Go to Sublime Text > Preferences > Settings.If the default behaviour is for Sublime Text to open files in new windows as opposed to the existing windows you have open, you can change this as follows: It can be disabled by going to System Preferences > Keyboard > Text > deselect “Add period with double-space” on the right.

This is a Sierra thing, not a Sublime Text thing. On macOS Sierra the default behaviour is for a full stop to be added when the space bar is pressed twice. To do this, right-click a file in Finder > Get Info > under “Open with:” find “Sublime Text” in the dropdown menu > click “Change All…” > Continue. In order to be able to open a file in Sublime Text by double-clicking it you need to make Sublime Text the default editor for its file type. You can open a file in Sublime Text from the terminal with: sublime
