Hello Wildermuth Salome (ewz)
Welcome to Microsoft Q&A Platform, thanks for posting your query here.
The Azure Cloud Shell editor is a great tool for editing files in Azure environment without having to install any software on your local machine.
The Monaco Editor is not preinstalled on the Ubuntu VM by default. However, you can install it manually on the VM.
Install Node.js and npm on the VM using the following command:
sudo apt-get update
sudo apt-get install nodejs npm
Install the Monaco Editor using npm
sudo npm install -g monaco-editor
Verify that the Monaco Editor is installed by running the following command:
monaco-editor
This should open the Monaco Editor in your default web browser.
Once you have installed the Monaco Editor, you can use it to edit files on the VM.
I hope this helps!