Crashes "Can’t find address book for group" in cases where that should not matter.

Here is the error:

https://matrix.to/#/!wAfwwonbRnRLYejFOR:gitter.im/$OSmTYbh0pLiyKCSDhev1jh3aASf2xHNiFc3FigPawwc?via=gitter.im&via=matrix.org&via=chat.semantic.works

points to a screencast video which shows (among other things) the error

 
Can’t find address book for group
in loadGroupsFromBook
in renderGroupMemberships
in renderIndividual