How to update jupyterlab using conda or pip?

You may need to specify conda-forge:

conda update -c conda-forge jupyterlab

EDIT: Trying to update to 3.0, conda update jupyterlab did not work for me (result of jupyter lab --version still was 2.x) and when I tried to specify conda-forge or jupyterlab=3.0 the command hung for too long. I gave up after almost an hour of solving environment. The following worked for me from the Anaconda shell:

conda uninstall jupyterlab
conda install -c conda-forge jupyterlab=3

conda update jupyter will not automatically update jupyterlab. You have to explicitly request an update of jupyterlab:

conda update jupyterlab