I just opened cmd as admin, opened jupyter lab and tried to install extansions but I got the same error again, I don’t know this is what you were asking, but it stills does not work this way
Would you mind opening a bug report on Issues · jupyterlab/jupyterlab · GitHub and adding in the JupyterLab version that you have installed? I think I know what the problem is (in JupyterLab).