When an ordinary user specifies TEXINPUTS in Overleaf [e.g., as illustrated here] is there a concept of a ".." directory above the current Project? The reason I would like to be able to do that is that I have image files, defs, and so on that I want to be able to draw on across all my Overleaf Projects, and I would prefer not to create separate copies of them to put in a ./includes//: inside whichever current Project I happen to be working.
To be clear, in my local texlive usage for those shared files I just use texmf/ in my login directory, but Overleaf of course doesn't have the notion of "my login directory". Or does it?