KeePassXC is an application for people with extremely high demands on secure personal data management. It has a light interface, is cross-platform and published under the terms of the GNU General Public License.
For known issues with the Snap install: https://github.com/keepassxreboot/keepassxc/issues?q=is%3Aissue+is%3Aopen+label%3A%22distribution%3A+Snap%22+
WARNING: There is currently an issue with some Linux distributions where you cannot open a file dialog or open a url when clicked. In this case you can downgrade to KeePassXC 2.6.6 using the candidate channel.