In Linux Mint, `cinnamon --replace` is a command to restart the desktop UI, including panels and applets [1][6]. It is not a command to replace the Cinnamon desktop environment, as the name might suggest [1].
It is a useful command when you encounter issues with the Cinnamon desktop, such as graphical glitches or unresponsive behavior.
When you run `cinnamon --replace`, it essentially stops the currently running instance of Cinnamon and then starts a new one. This can help resolve minor issues without the need to log out or reboot your computer.
Here's how to use the `cinnamon --replace` command:
1. Press `Ctrl + Alt + F2` to access a virtual terminal (TTY) or open a terminal window from your desktop environment.
2. Log in with your username and password.
3. Run the following command to replace the Cinnamon desktop:

    cinnamon --replace

4. Wait a few moments for Cinnamon to restart.
5. You should see the desktop environment refresh, and any issues you were experiencing may be resolved.

If you are facing issues with the cinnamon --replace command or if it doesn't resolve the problem you are encountering in the Cinnamon desktop environment in Linux Mint, you can try the following steps to troubleshoot and resolve the issue:
1. Reboot Your Computer:
Sometimes, issues with the desktop environment or system processes can be resolved simply by rebooting your computer. Restarting can clear temporary system glitches.
2. Check for Updates:
Ensure that your Linux Mint system is up to date by running the following commands:

    sudo apt update
    sudo apt upgrade

After updating, reboot your system.
3. Check System Resources:
Insufficient system resources (CPU, RAM) can lead to desktop issues. Check the system monitor for any resource-heavy processes and close unnecessary applications.
4. Reset Cinnamon Settings:
If the problem persists, you can reset your Cinnamon settings to their default values. Open a terminal and run:

    cinnamon --replace --reset

This command will reset your Cinnamon settings and restart the desktop environment.
5. Check Logs:
Review the system and desktop environment logs for any error messages or warnings. You can access these logs using commands like `journalctl` or by checking log files `in /var/log`.

To generate an overview of your system, you can launch a terminal window and enter the command `inxi -Fxz` to get information about your system's hardware and software configuration [2].
If you are experiencing high CPU usage from the `cinnamon --replace` process, it may be helpful to try restarting the process or switching to a different desktop environment, such as MATE or XFCE [6].