alt Hacker Newspersonally have been placing a paperclip icon when clicking something opens a new tab / window. idk why, felt like the best from the icon set
if the link just navigates to another page, imo it doesnt need an icon at all (and should be reconsidered: why a new page?)
A physical paperclip collects things that aren't otherwise connected. For example, I receive a printed paper several pages long all stapled together, and I want to add a small note before passing along or returning, then I'd probably use a paperclip to attach my small note to the document. I don't think a paperclip icon in any way communicates "this will be a new window/tab when clicked."