The render thread is not shown by default on a "gfx" preset profile

(Moving the [Bug 1804444](https://bugzilla.mozilla.org/show_bug.cgi?id=1804444) to here)

See the default profile : https://share.firefox.dev/3BiwQ7E

Notice that only "cdpn.io" and "CanvasRenderer" are visible.

Now, enable all the threads. You will see that there is heavy jank on the "Renderer" thread. See the profile: https://share.firefox.dev/3PmXbHP

ER: If a thread is so heavily janked, it should be visible by default (atleast for all "graphics-y" threads)

┆Issue is synchronized with this [Jira Task](https://mozilla-hub.atlassian.net/browse/FP-599)