Pre-installed extensions?

just a quick question:
Does the JupyterLab come with pre-installed extensions? (default extensions)

Because this is what I see, when I click “enable” extensions:
(I am new to JupyterLab, and I am not aware of having installing any of this.
I just want to be sure it is okay, since there is even a warning about running third-party extensions… Thank you.)

A look at the User Guide has descriptions and screenshots of all the core features, which you get when you pip install jupyterlab (or conda install jupyterlab). These are generally considered the “core” features, though some of them (like multi-user editing) require some additional configuration.

All those other extensions are likely “prebuilt extensions,” which were installed when you or your administrator ran pip install ipywidgets or pip install plotly, or some package that depended on those. They can be disabled with jupyter labextension disable <npm package name>, but as they “belong” to python packages, it might confuse pip or conda to fully uninstall them.

but as they “belong” to python packages

And the “About” button should show to which package they belong. If it does not, please report it to extension maintainer.