Do not open Notebook in new Tab

Hi,

Every time I click on a `*.ipynb` file via the web browser, it opens the file in a new tab. Usually I end up in a situation where multiple instances of the same notebook are open. Is it possible to prevent Jupyter doing so? I would prefer the native "Open Link in a new Tab" functionality if I really need it. A quick solution would be to remove all `target="_blank"` but is there also an option for that?

Greetings
René

No file, test, or entry point is named. Start by tracing how the web interface generates links for .ipynb files, then verify that normal clicks reuse the current tab while an explicit browser “Open Link in a new Tab” still works.

Written by the indexing model from the issue text.