[Evolution] Calendar is read-only

[Lucas Eichhorn <eichhorn l gmx de>]

Hi!
I was looking for alternatives to TB (on Ubuntu) and came across
Evolution. Looks pretty nice and it also has the must-have calendar
feature. However it seems to stay in “read-only”, I tried 3 ways of
adding it. Which means I cannot add/edit events and that makes the
calendar useless to me. I searched a bit online but couldn't find a
solution. Could you help me out? Am I doing something wrong? The
calendars I want to add are Google calendars and I tried the options of
adding: Google, On The Web, CalDAV.
Best! :)