Hi there,
If your original URL has been contain the SourceID parameter, you can set the HttpReauest in the Source in the GoToURL setting, then the GoToURL will contain the SourceID parameter that catch the value form the original URL.
About the Source parameter, because the URL needs to carry the SourceID parameter, so it cannot be hardcoded in the GoToURL setting, unfortunately, it doesn’t support the parameter configuration in this scenario. I think you could try to write some special script in the target page, for example, if you can hardcode some special parameter in the GoToURL setting:
http://sitex/SitePages/Navigation/TaskNewItem.aspx?SourceType=Project&needToSetSource=true&Source= sitex/.../ProjectPortal.aspx
and you also has set the HttpRequest parameter into the GoToURL setting, and now, if you click the GoToURL button, the real URL should be: http://sitex/SitePages/Navigation/TaskNewItem.aspx?SourceType=Project&needToSetSource=true&Source= http://sitex/SitePages/Navigation/ProjectPortal.aspx &SourceID=30 Then in the target page, write some script to detect the “needToSetSource” parameter, if exist, then construct the ‘Source’ URL to Source= sitex/.../ProjectPortal.aspx&SourceID=30
Then reload it.