Is it best to open all external references in new tabs by default?

In my security webapp chausies.xyz/encrypt, I have the main webapp without any clutter for the general user, and then, at the bottom of the page, I list a bunch of external security references in case anyone wants to dig deeper or learn more about the security used by the app. Currently, I have these sending the user to a new tab by default (with target="_blank"), but is this as it should be? My reasoning is that all these link to wikipedia and other places that have nothing to do with actually using the webapp. And, for security purposes, the website loads with all forms cleared every time, so going "back" to the website is the same as just opening it again.

Similarly, in the security overview for the webapp, it's filled with a bunch of references (external links) to wikipedia and random open source code. Should it be the case that all these external references send the user to a new tab?

This question is relevant to mine, but I am specifically interested in my case, where the items are all external security references which are all side-reading that has nothing to do with using the webapp itself, and the webapp itself has all of its forms cleared on every load for security purposes (detracting from the argument that users can "just go back" if things were kept on the same tab).