I think Discourse may support this, there are some mentions of it on their own support pages back in April. It looks like there was an issue however with links that were clicked on rather than keyboard use.
There is a post in the Unity forum regarding a bowling issue, the link to the OPs video opens in a new tab for me.
I wonder whether perhaps external links are opening in a new tab, but internal links are not?
Internal: Pins not resetting after Renew and Pins being hit during Tidy. Video inside
Yep… that appears to be the case.
Of course, you would only want links within posts to open in a new tab, not the links to other courses/sub-forums, that would get a bit crazy…