Steps:

• use snaps from automatic update : snap install keepass-xc
• start, open a database
• in general options, enable browser integration
• install KeePassXc-Browser extension for Firefox or Chrome
• download, grant permission and execute the shell link script (KeePassXC <=> KeePassXC-Browser)
• restart OS
• open KeePassXC, unlocking a database for which an entry possess an URL
• open browser and key the URL
• on KeePassXC-Browser, click Connect
• check the credentials are filled in

KeePassXC can store SSH passphrases, and register SSH keys (ssh-add) accordingly

Steps:

• check ssh agent is running pgrep -a ssh-agent
• check ssh agent socket is declared env | grep SSH_AUTH_SOCK
• KeePassXC / General setings : Enable SSH integration => should turn green
• restart KeePassXC
• in database, create an entry, supplying the passphrase as password
• in database entry, go to SSH agent tab
• enter path to SSH PRIVATE key in External file
• go back to database view
• on entry, right-click then Add key to SSH agent (Ctrl H)
• check key has been added ssh-add -l
• then click Remove key to SSH agent (Ctrl Shift H)
• check key has been removed ssh-add -l