Jeremy Tuloup

Done in https://github.com/jupyter/notebook/pull/7423/commits/40387bbef7387b5a79103b6edeae0f5e59b9a4e9. Although not seeing any change for now: 

Is there a way to reduce the size of the "File size" column? I guess it's related to https://github.com/jupyterlab/jupyterlab/pull/16646 ? 

> Although not seeing any change for now: This change of background color is also picked up in the UI tests, so it's not a local dev environment issue only:...

> This change of background color is also picked up in the UI tests, so it's not a local dev environment issue only: It looks like `.jp-ThemedContainer` was taking precedence...

Arf, looks like there are more CSS regressions to fix, for example the menus are now gray and there is no styling on hover: 

> Is there a way to reduce the size of the "File size" column? I guess it's related to [jupyterlab/jupyterlab#16646](https://github.com/jupyterlab/jupyterlab/pull/16646) ? I guess it's because Notebook 7 does not provide...

@krassowski any suggestion for setting proper defaults for the file browser column sizes? I tried something like the following but it didn't seem to have any effect: ```ts stateDB.save('file-browser-filebrowser:columns', {...

Or maybe this will be made easier with https://github.com/jupyterlab/jupyterlab/pull/16751, so we can just specify custom CSS directly instead.

The file browser looks great now after the `4.3.0b3` update:  Thanks @krassowski @JasonWeill for working on this!

bot please update playwright snapshots