In recent years, Anaconda has provided two offline upgrade installation packages every year. Two days ago, when the first installation package in 2023 came, it was downloaded and installed. I thought it was just an ordinary operation, but I still encountered the "magic" side.

Uninstall the old version of Anaconda and install the new version

First of all, my machine is a Win10 operating system, Anaconda3-2022.10 is installed, and the Python version is upgraded to 3.9.16. This time, Python in Anaconda has achieved a "major version upgrade", that is, it has been upgraded from 3.9 to 3.10. If you have installed a version older than Anaconda3-2023.03, you need to uninstall it and install Anaconda 3-2023.03 to achieve the upgrade. Now rely on conda update is not upgraded to 3.10 . Of course, you can also keep the original installation and specify another directory to install Anaconda3-2023.03. Since I installed Anaconda just for learning, I uninstalled Anaconda3-2022.10.
Uninstallation and installation went smoothly. After installation, Python is 3.10.9, Spyder is 4.5.1, and there are six shortcuts in the menu, including "Anaconda Navigator", "Anaconda Powershell Prompt", and "Spyder".

Magic one, the first update after Anaconda is installed becomes Miniconda.

After installation, I opened the "Anaconda Powershell Prompt" by " running as an administrator " and updated it...

(base) PS C:\windows\system32> conda update --all

Seeing a long list of package downloads and package removals in the prompt, there are so many, "Isn't that what the so-called update is?", I pressed Enter to agree without looking carefully. After the update, there are only three shortcuts left in the menu bar:

"Jupyter Notebook" and "Spyder" shortcuts are missing. Enter "Anaconda Navigator", the three applications originally installed by default are not installed. (almost executed conda uninstall spyder)

(base) PS C:\WINDOWS\system32> conda update anaconda

PackageNotInstalledError: Package is not installed in prefix.
  prefix: C:\ProgramData\anaconda3
  package name: anaconda

The anaconda package was actually lost.
So, reinstall it:

(base) PS C:\WINDOWS\system32> conda install anaconda

Click "Start", and several shortcuts that were lost in the menu bar are back.
Perform the update again conda update --all

(base) PS C:\WINDOWS\system32> conda update --all
Collecting package metadata (current_repodata.json): done
Solving environment: done

# All requested packages already installed.

(base) PS C:\WINDOWS\system32>

No fuss this time.

Magic 2, there are base environment and anaconda environment?

But no.

(base) PS C:\Users\Administrator> conda env list
# conda environments:
#
                         C:\ProgramData\Anaconda3
base                  *  C:\ProgramData\anaconda3

In the magic three Spyder dependencies, some optional modules need to be installed manually

Manually install missing optional modules

conda install cython

(PS: I installed it again under Win11, and these "magic properties" still exist. After Anaconda3-2023.03 is successfully installed, the first conda update --all operation will delete spyder and its mandatory dependencies and installed optional dependencies , Anaconsa almost becomes Miniconda)