v3 Plugin becomes very slow and even lags on large schema

**Intended outcome:**
In the previous version of the Apollo Client Devtools Chrome plugin (I guess v2?), I could type and run queries pretty quickly; there was no visible lag. Of course the introspection query did take some time to populate, but that was okay. Auto-suggestions worked quickly.

**Actual outcome:**
In this new version, even typing queries into the workspace becomes a challenge. Constant lagging (registering my keystrokes a second or two after I enter them), sometimes even freezing the Chrome window I'm working in.

**How to reproduce the issue:**
Happens every time I try to use the devtools. I am working with a fairly large schema (schema.json is 6.5MB for reference), but it was working fine before the upgrade to v3.

**Desktop (please complete the following information):**
- OS: Ubuntu 18.04
- Browser: Chrome
- Browser version: Chrome Version 89.0.4389.90 (Official Build) (64-bit)
- Extension version: 3.0.2

Start by reproducing the lag in the v3.0.2 Chrome extension with the reported 6.5MB schema.json, then compare typing and auto-suggestion behavior with the previous version. Done means queries can be entered and suggestions appear without the reported delays or freezing on a large schema.

Written by the indexing model from the issue text.