Ok so this shit happened to me on two occassions the last few days. Not sure when it started, but it seems that if I paste a link directly (without clicking the hyperlink-button), sometimes the link just doesn't get converted correctly after I continue typing, and instead the rest of the post will be lost. OFC I cannot reproduce it reliable now, but I've had to retype stuff like 5 times and it is really infuriating. One of the posts in question is https://www.gamedev.net/forums/topic/714764-fixed-timestep-with-interpolation-2d-movement-jitterstutter/5458498/.​

Think I figure out out. If you post a link, and then immedately make a half-linebreak (shift+enter; before the link becomes blue), it bugs the entire editor out:

https://www.gamedev.net/forums/topic/714787-pasting-a-link-results-in-rest-of-post-being-lost/5458499/
So

https://gamedev.net/forums/topic/714457-why-is-the-site-so-slow/5457548/

FWIW, the editor is completely outsourced (CKEditor).

I've been debating replacing it, but it does some things other editors would require a lot more work to support.. so, that's what we have. It's been a little while since it's been upgraded though, so I can see if this problem has been resolved in more recent versions.