Cannot edit a newly created toolchain

Steps to reproduce:

# conda install beat beta versions
git clone git@gitlab.idiap.ch:beat/beat.tutorial.prefix reproduce-issues
cd reproduce-issues
beat config set --local prefix $PWD/prefix
beat editor start
# answer yes to confirmations
# go to file, new, toolchain
# create a new toolchain named test_lda
# try adding a block to the toolchain

You may also watch the attached video Peek_2020-05-27_12-39