Failed to install electerm using snap on Ubuntu

After I download the snap file "electerm-1.3.1-linux-amd64.snap" from this url, I get the following error shown in the snapshot below using command:

sudo snap install electerm-1.3.1-linux-amd64.snap

To fix such an error, the option --dangerous is used to force the command not to verify the installation signature:

sudo snap install --dangerous electerm-1.3.1-linux-amd64.snap

In summary, to resolve the error "cannot find signatures with metadata for snap" when installing using snap, you can use the flag --dangerous

Credits: Kyle, and electerm

***Note***: I encounter one problem; it is unable to use the command "sudo", and other commands as shown in below snapshot when using in electerm with error permission denied:

So I decide to uninstall with the following command:

sudo snap remove electerm

Once I download deb package from this link, I simply install it by the following command:

sudo dpkg -i  electerm-1.3.4-linux-amd64.deb

Then the problem of "permission denied" is gone, and I can normally use all the commands:

As of March 24, 2020, the version electerm-1.3.4-linux-amd64.deb is available for download from this link