ssid@ discovered a massive net memory leak by using a combination of native [more detail] /virtual [faster, less overhead] heap profiler on Linux.
https://docs.google.com/document/d/1XKx4-AMBxPxfJ0jDlBlqiWGNbl6-AFNvNceLvlx4mvM/edit#heading=h.mjnvjkg9w4dp

Once we have it working on Windows and macOS, let's try the same thing. The details are something like: One browser window, 50 tabs, let Chrome idle for a week. ssid@ can fill us in on details.

We've certainly heard reports of 4GB+ heap size in the browser process on macOS, I imagine Windows is comparable.