New button crashes

When I click "New", I get this error:

ERROR 19:24:41 project           New Project _get_caps_from_feature: theoraenc not in registry (project.py:957)
Traceback (most recent call last):
  File "/usr/lib64/pitivi/python/pitivi/dialogs/startupwizard.py", line 123, in _deleteCb
    self.app.project_manager.newBlankProject()
  File "/usr/lib64/pitivi/python/pitivi/project.py", line 519, in newBlankProject
    project = Project(self.app, name=DEFAULT_NAME)
  File "/usr/lib64/pitivi/python/pitivi/project.py", line 724, in __init__
    self._ensureVideoRestrictions()
  File "/usr/lib64/pitivi/python/pitivi/project.py", line 1722, in _ensureVideoRestrictions
    prev_vals)
  File "/usr/lib64/pitivi/python/pitivi/project.py", line 1688, in _ensureRestrictions
    encoder_sinkcaps = encoder.sinkpads[0].get_pad_template().get_caps().copy()
AttributeError: 'NoneType' object has no attribute 'sinkpads'

I installed pitivi from gentoo official repositories. Uname:

Linux Rakija 5.8.18-gentoo.numa #7 SMP Fri Dec 11 13:33:47 CET 2020 x86_64 AMD Ryzen 5 2600 Six-Core Processor AuthenticAMD GNU/Linux