location.href and top.document.referer seem to be already URL encoded. At least in the browsers we tested. When tracking, we do encode them again meaning they are double url encoded which is wrong. Even worse some browsers use uppercase and some browsers use lowercase for the url encoding meaning we store 2 actions for the same URL. See #7209 . It also causes that it is not possible to segment for those URLs see #7218

Solution should be most likely to always url-decode the url and referrer before url-encoding them again (which is done when the request is sent)