page/page.go
func (p *GetAppManifestParams) Do(ctx context.Context) (url string, errors []*AppManifestError, data string, err error) {
	// execute
	var res GetAppManifestReturns
	err = cdp.Execute(ctx, CommandGetAppManifest, nil, &res)
	if err != nil {
		return "", nil, "", err
	}

	return res.URL, res.Errors, res.Data, nil
}
func (p *GetAppManifestParams) Do(ctx context.Context) (url string, errors []*AppManifestError, data string, err error) {
	// execute
	var res GetAppManifestReturns
	err = cdp.Execute(ctx, CommandGetAppManifest, nil, &res)
	if err != nil {
		return "", nil, "", err
	}

	return res.URL, res.Errors, res.Data, nil
}
// Do executes Page.getAppManifest against the provided context.
//
// returns:
//   url - Manifest location.
//   errors
//   data - Manifest content.