Seems like this release also breaks stuff, ipywidget CI doesn't run: * https://github.com/jupyter-widgets/ipywidgets/pull/3642 jdaviz (ipywidget based) is completely broken: * https://github.com/spacetelescope/jdaviz/pull/1876 I'm looking into it, but better to avoid many unhappy users.