The same thing happens to me.

What I do (at least for a while, until I forget) is to open a link to a thread in a new tab, so that the search results remain on their own tab.

Inevitably I forget to do this, and then much cussing ensues, but it's a workaround.

On a Mac, I hold down Command while clicking the link. I've forgotten off the top of my head how to do this in Windows, but it's equally simple. Control key, probably.