sudo apt-get install chrome-gnome-shell
Now go to https://extensions.gnome.org/
Install required extensions after downloading the browser extension. In case of firefox, you may need to disable extension compatibility checking.
You can control extensions and their settings from gnome-tweak-tool
In case of serious issues preventing booting:
apt-get install --reinstall gdm3 gnome gnome-shell
You may also want to move everything from ~/.local/share/gnome-shell/extensions
The lower left corner legacy icons are an irritation. To move them, install the GNOME shell extension TopIcons. This moves the legacy tray icons shown in this bar to the main GNOME bar, up in the top right by the menu.