Bloom.Browser.LoadPageDomFromBrowser C# (CSharp) Method

        private void LoadPageDomFromBrowser()
        {
            Debug.Assert(!InvokeRequired);
            if (_pageEditDom == null)
                return;

            GeckoDocument contentDocument = null;
            try
            {
                if (_pageEditDom == _rootDom)
                    contentDocument = _browser.Document;
                else
                {
                    // Assume _editDom corresponds to a frame called 'page' in the root. This may eventually need to be more configurable.
                    if (_browser.Window == null || _browser.Window.Document == null)
                        return;
                    var frameElement = _browser.Window.Document.GetElementById("page") as GeckoIFrameElement;
                    if (frameElement == null)
                        return;
                    // contentDocument = frameElement.ContentDocument; unreliable in Gecko45
                    contentDocument = (GeckoDocument) frameElement.ContentWindow.Document; // TomH says this will always succeed
                }
                if (contentDocument == null)
                    return; // can this happen?
                // As of august 2012 textareas only occur in the Calendar
                if (_pageEditDom.SelectNodes("//textarea").Count > 0)
                {
                    //This approach was to force an onblur so that we can get at the actual user-edited value.
                    //This caused problems, with Bloom itself (the Shell) not knowing that it is active.
                    //_browser.WebBrowserFocus.Deactivate();
                    //_browser.WebBrowserFocus.Activate();

                    // Now, we just do the blur directly.
                    var activeElement = contentDocument.ActiveElement;
                    if (activeElement != null)
                        activeElement.Blur();
                }

                var body = contentDocument.GetElementsByTagName("body");
                if (body.Length ==0)	//review: a previous comment said this could happen in OnValidating, but that is gone...may be obsolete
                    return;

                var content = body[0].InnerHtml;
                XmlDocument dom;

                //todo: deal with exception that can come out of this
                dom = XmlHtmlConverter.GetXmlDomFromHtml(content, false);
                var bodyDom = dom.SelectSingleNode("//body");

                if (_pageEditDom == null)
                    return;

                var destinationDomPage = _pageEditDom.SelectSingleNode("//body//div[contains(@class,'bloom-page')]");
                if (destinationDomPage == null)
                    return;
                var expectedPageId = destinationDomPage.Attributes["id"].Value;

                var browserDomPage = bodyDom.SelectSingleNode("//body//div[contains(@class,'bloom-page')]");
                if (browserDomPage == null)
                    return;//why? but I've seen it happen

                var thisPageId = browserDomPage.Attributes["id"].Value;
                if(expectedPageId != thisPageId)
                {
                    SIL.Reporting.ErrorReport.NotifyUserOfProblem("Bloom encountered an error saving that page (unexpected page id)");
                    return;
                }
                _pageEditDom.GetElementsByTagName("body")[0].InnerXml = bodyDom.InnerXml;

                var userModifiedStyleSheet = contentDocument.StyleSheets.FirstOrDefault(s =>
                    {
                        // workaround for bug #40 (https://bitbucket.org/geckofx/geckofx-29.0/issue/40/xpath-error-hresult-0x805b0034)
                        // var titleNode = s.OwnerNode.EvaluateXPath("@title").GetSingleNodeValue();
                        var titleNode = s.OwnerNode.EvaluateXPath("@title").GetNodes().FirstOrDefault();
                        if (titleNode == null)
                            return false;
                        return titleNode.NodeValue == "userModifiedStyles";
                    });

                if (userModifiedStyleSheet != null)
                {
                    SaveCustomizedCssRules(userModifiedStyleSheet);
                }

                //enhance: we have jscript for this: cleanup()... but running jscript in this method was leading the browser to show blank screen
            //				foreach (XmlElement j in _editDom.SafeSelectNodes("//div[contains(@class, 'ui-tooltip')]"))
            //				{
            //					j.ParentNode.RemoveChild(j);
            //				}
            //				foreach (XmlAttribute j in _editDom.SafeSelectNodes("//@ariasecondary-describedby | //@aria-describedby"))
            //				{
            //					j.OwnerElement.RemoveAttributeNode(j);
            //				}

            }
            catch(Exception e)
            {
                Debug.Fail("Debug Mode Only: Error while trying to read changes to CSSRules. In Release, this just gets swallowed. Will now re-throw the exception.");
            #if DEBUG
                throw;
            #endif
            }
            finally
            {
                if (contentDocument != null)
                    contentDocument.Dispose();
            }

            try
            {
                XmlHtmlConverter.ThrowIfHtmlHasErrors(_pageEditDom.OuterXml);
            }
            catch (Exception e)
            {
                //var exceptionWithHtmlContents = new Exception(content);
                ErrorReport.NotifyUserOfProblem(e,
                    "Sorry, Bloom choked on something on this page (validating page).{1}{1}+{0}",
                    e.Message, Environment.NewLine);
            }
        }