Chrome tab memory keeps growing, heap size stays the same
This is probably too old and not relevant anymore, but for everyone else who experienced this: it's probably because of the opened dev tools. I had an application that would accumulate memory over time with the heap size staying the same, but when I closed the dev tools the memory went way down and didn't get back up like it did when dev tools was open. When profiling long term memory footprint, use chrome task manager first.
I can guess that in your case it happens because devtools has to store all those REST API calls (to show them in Network tab) and I'm not sure if chrome saves them to disk temporarily to save memory.