To us, this is an important read because we find we are in so many situations with clients questioning if a link opens in a new window or not. For the most part we advice against it, particularly for the mobile experience. It great to find this recent article from the Nielsen Norman Group, our authority on all things UX, about when not to allow this link behavior:

Since 1999, it's been a firm web-usability guideline to refrain from opening new browser windows for several reasons. All of these also apply to opening new browser tabs and are still valid today:

  • More windows or tabs increase the clutter of the user’s information space and require more effort to manage.
  • New windows or tabs can cause disorientation, with users often not realizing that a new window or tab has opened. This problem is exacerbated on mobile, where the old window is never visible.
  • Less-technical users struggle to manage multiple windows and tabs, especially on mobile. (On tablets, where users can have both multiple windows and tabs for the browser, it’s even more confusing.)
  • New windows or tabs prevent the use of the Back button for returning to the previous page and force the user to spend effort to find their way back to the previous content.
  • New windows or tabs are not inclusive for blind or low-vision users — especially when they open outside of the area that's magnified.

More: https://www.nngroup.com/articles/new-browser-windows-and-tabs