Once we enable the JSWindowActor based targets, will-navigate and navigate starts missing.
We should get away from these events and especially navigate which is very unreliable.

These events are used in tests over here, and break when enabling bug 1698891:
https://searchfox.org/mozilla-central/rev/6cbe34b441f7c7c29cd1e5f0e19c7000142f1423/devtools/client/netmonitor/test/head.js#202-210

function waitForNavigation(target) {
  return new Promise(resolve => {
    target.once("will-navigate", () => {
      target.once("navigate", () => {
        resolve();
      });
    });
  });
}

Here we should rather only wait for the next DOCUMENT_EVENT's dom-complete.

We should probably also do the exact same thing in this production code:
https://searchfox.org/mozilla-central/source/devtools/client/netmonitor/src/connector/index.js#463-468

    // Waits for a series of "navigation start" and "navigation stop" events.
    const waitForNavigation = async () => {
      await this.currentTarget.once("will-navigate");
      await this.currentTarget.once("navigate");
    };

Actually, bug 1708635 will cover this.