I have several computers and Android phones that have bookmarks synced by Xmarks. My Chrome browser on my Android Nexus 6 currently contains hundreds of bookmarks that I collected on other computers years before I bought the Nexus 6. But in chrome they do not update so they apparently don't sync with the others.

I was told on the Nexus 6 forum that Chrome doesn't run extensions for Android and it is not possible to sync bookmarks with Android-Chrome. Those bookmarks in my android Chrome had to have come from somewhere. If not an extension, then some other mechanism put them there. I want to find out what controls those bookmarks so I can bring them up to date. If not by syncing, then by whatever method works.