If you feel like Chrome's been using more RAM on the desktop client since the v67 release a month back, good news: you're not going crazy! Bad news: it definitely is using more RAM (again, on the desktop).
That's because of an advanced new security feature the Chromium team has rolled into the latest version of Google's infamously memory-hungry browser, known as Site Isolation. I'll spare you the technical details, but the short of it is that because the growing number of memory leak vulnerabilities being exposed as part of the Spectre and Meltdown flaws, the Chrome team has decided to enable Site Isolation by default in Chrome on the desktop as of version 67.
Site Isolation prevents a website from potentially accessing data on another website by running the two in isolated processes, which is apparently a pretty crazy technical achievement according to Google's head of Chrome Security, Justin Schuh. You can see a basic visual representation of the feature in the image below, which I have to think tragically undersells just how complicated this was to do.
Schuh also says this feature isn't coming to the Android version of the browser yet because - wait for it - they have concerns about resource consumption (shocking).
Technical highlights: The current version defends only against data leakage attacks (e.g. Spectre), but work is underway to protect against attacks from compromised renderers. We also haven't shipped to Android yet, as we're still working on resource consumption issues.
— Justin Schuh 😑 (@justinschuh) July 11, 2018
While this new Site Isolation feature is obviously a benefit from a security standpoint, it's pretty comical to see Chrome's memory usage continue to creep ever-upward.
For more, you can read the full writeup on Chromium Security site, or the Google Security Blog, linked below.