Open documents as tabs into the same / existing window
Whenever I'm opening text files in Nautilus and Gedit is not already focused, or is on a separate workspace, it creates a new gedit windown instead of opening the document into a tab in the existing gedit window. This is supremely annoying because multiple times per day, I end up having 3-4 gedit windows open across multiple workspaces instead of it just being brought to the current workspace (or me being switched to a different workspace), and the whole point of tabs for me is to not have to do window management!
Furthermore, moving/merging tabs across windows is not fun, you have to open the sidebar on each window, put each window on the same workspace, then drag tabs from one sidebar to another and then close the now empty window. A big waste of time. Not to mention the usability issues that having multiple windows cause by having the user attempt to reopen the same document because they don't see it in their current set of tabs, such as issue #157 and issue #75 ... those could be just nuked.