Snap is a cross-platform packaging and deployment system developed by Canonical, the makers of Ubuntu, for the Linux platform. It’s compatible with most major Linux distros, including Ubuntu, Debian, Arch Linux, Fedora, CentOS, and Manjaro.
Snaps reside in the Snap Store, and you can explore and download them just like you do with other package managers. Additionally, you also get the option to publish your own snap packages directly to the Snap Store, which is not possible with traditional package managers.
Application update shows error dialog with text: Unable to update “Snap Store”: (null): cannot refresh “snap-store”: snap “snap-store” has running apps (ubuntu-software)
Open the Terminal and type the following commands.
killall snap-store snap refresh