The following plugins are now Bootstrap 4 ready.
CB Profile Update Logger
CB Progress Field
CB Last Views Tab
CB Invites
CB Auto Actions
CB Gravatar Field
CB Privacy
CB Connect
Still plenty more to go, but so far looks like still on track for release by end of this month (hopefully!). Trying to get all the smaller easy to upgrade plugins out of the way first before digging into the larger plugins like CB Activity, CB Gallery, and CB GroupJive which all have heavy styling to deal with.