If your Ubuntu version or derivative has not packaged Inkscape 1.3 for you yet, you can install the current version from our ppa for Ubuntu 20.04, 22.04, 23.04 and 23.10:

Desktop Instructions

1. Start the application "Software and updates"
2. Select the tab "Other Software"
3. Click the button "Add..."
4. Enter the following text

   ppa:inkscape.dev/stable

5. Click the button "Add Source"
6. Click on the button "Close"
7. When the pop up warns "The information about available software is out-of-date" click the button "Reload"
8. The latest stable version of Inkscape is now avaialble to be installed from the software center.

Command Line

sudo add-apt-repository ppa:inkscape.dev/stable
sudo apt update
sudo apt install inkscape