In modern browsers, if I click on a link in an article that I'm reading and I'm taken there, I can press back to go back to where I came from. If I decide to open it in a new background tab (so I can finish the article and then read the newly opened tab), that new tab will have its history erased. Why? I would like it to stay so I could press back and figure out where I came from.

It happens quite often that I end up trying to find where I came from on a tab that happened to be opened as new, and hence has no back history. (One hack that I've learned to avoid this problem in desktop Chrome is to duplicate the tab, then click a link regularly. This preserves the back history.)