If you experience high memory, high CPU, or any other performance issues (sluggish behavior, unresponsive pages, etc), taking a heap profile of Studio will be the most helpful way to help us track it down. In order to take a heap profile, you'll need to open your browser's developer tools.
Once your browser Developer Tools are open, select the "Memory" tab.
Under the Memory tab, you should see the option to take a "Heap snapshot" profile. With "Heap snapshot" chosen, select the Javascript VM instance with the highest memory utilization, and then hit the "Take snapshot" button.
Once the snapshot is completed, click the "Save" button next to the snapshot. Once saved, send the resulting snapshot to Stoplight support to have it analyzed.