Method _detachContentWhenEmpty

src/cdk/overlay/overlay-ref.ts:523–553

Detaches the overlay once the content finishes animating and is removed from the DOM.

()

  /** Detaches the overlay once the content finishes animating and is removed from the DOM. */
  private _detachContentWhenEmpty() {
    let rethrow = false;
    // Attempt to detach on the next render.
    try {
      this._detachContentAfterRenderRef = afterNextRender(
        () => {
          // Rethrow if we encounter an actual error detaching.
          rethrow = true;
          this._detachContent();
        },
        {
          injector: this._injector,
        },
      );
    } catch (e) {
      if (rethrow) {
        throw e;
      }
      // afterNextRender throws if the EnvironmentInjector is has already been destroyed.
      // This may happen in tests that don't properly flush all async work.
      // In order to avoid breaking those tests, we just detach immediately in this case.
      this._detachContent();
    }
    // Otherwise wait until the content finishes animating out and detach.
    if (globalThis.MutationObserver && this._pane) {
      this._detachContentMutationObserver ||= new globalThis.MutationObserver(() => {
        this._detachContent();
      });
      this._detachContentMutationObserver.observe(this._pane, {childList: true});
    }
  }

  private _detachContent() {
    // Needs a couple of checks for the pane and host, because