Without installing Linux Mint 19.x, you can try out Cinnamon Desktop 4.2 in Ubuntu 19.04 or Ubuntu 18.04 via the PPA repository.
Cinnamon 4.2 features less RAM usage, Muffin optimizations, switch VSYNC on or off without restart, faster application menu, samba improvements, and many other improvements.
Install Cinnamon 4.2 via PPA in Ubuntu:
NOTE the PPA contains UNOFFICIAL (though probably the next best thing after official) builds of Cinnamon releases for Ubuntu 18.04 and Ubuntu 19.04 so far.
1. Open terminal either from application menu or by pressing Ctrl+Alt+T on keyboard. When it opens, run command to add the PPA:
sudo add-apt-repository ppa:embrosyn/cinnamon
Type user password (no asterisk feedback) for sudo prompt and hit Enter to continue.
2. Then install Cinnamon desktop via command:
sudo apt install cinnamon
Once installed, log out and login with Cinnamon session.
Uninstall:
To remove Cinnamon desktop, run command:
sudo apt remove --autoremove cinnamon cinnamon-desktop-data
To remove the PPA, either go to Software & Updates -> Other Software, or run command:
sudo add-apt-repository --remove ppa:embrosyn/cinnamon
