That's possible. I'll add this: Edge in general has really slowed down for me, and not just on my SB2. I think Microsoft also updated it to mitigate for Meltdown (I think that's the one that can use the browser to exploit). I'm fairly certain that Edge wasn't doubling RAM use prior to the update, but I could be mistaken.As an experiment- I switched to using the NVIDIA GPU as the default and any lag I was experiencing went away with Edge. It's possible the CPU patch has impacted the Intel GMA.
Right now, Firefox 59 is SIGNIFICANTLY faster. I mean, it's night and day. Even typing into a text box in Edge is slow but speedy in Firefox. I should probably test Chrome as well, but I'm kind of fed up with Chrome right now.