Force Safari to open target links in new tab rather than window
You can force Safari to open target = “_blank” links into new tabs rather than new windows by opening the Terminal and typing the following command:
defaults write com.apple.Safari TargetedClicksCreateTabs -bool true
Then restart Safari and from here on anytime you click a link targeted as _blank it will open in a new tab.
You can reverse this behavior and go back to the default new windows instead by typing:
defaults write com.apple.Safari TargetedClicksCreateTabs -bool false
I think opening these links in a tab makes a lot of sense and I’m not sure why Safari defaults to new windows, or has this feature so hidden.

Nice one. You can also hold command when you click. If you have the status bar displayed at the bottom of Safari you’ll see it change to new tab when you hover with Command pressed.
[...] trick oczywiście nie jest mojego autorstwa, pochodzi z OS X Daily, ale postanowiłem go “przepisać” ze względu na to, że jest to bardzo przydatna [...]
[...] Force Safari to open target links in new tab rather than window [...]