Available for Chrome and Firefox.
HN Card lets you quickly glance at a user's profile without leaving the page you're on. You can quickly see a user's bio, karma, account age - plus quick links to their comments and submissions. Plus, if they have an email address or Github account in their bio (providing they've set up a Gravatar or Github avatar), you'll see their avatar too.
HN Card is available for Chrome and Firefox. You would want to grab a copy from the appropriate extensions / addon store.
I thought this feature would be cool on HN, so wanted to implement it but a quick google search led me to the above forked repository, but couldn't install on firefox
So this repo is simply an attempt to update the extension, and fix a few errors. All credit to Tim Davies
Download here: https://chrome.google.com/webstore/detail/hn-card/medlpimkoihjpkajkdlkjmphcdgldgkm
Download here: https://addons.mozilla.org/en-US/firefox/addon/hn-card
Clone or download this repository, open chrome://extensions (type in address bar), click "Load Unpacked", then select the chrome folder.
Clone or download this repository, open about:debugging (type in address bar), click "This Firefox", then "Load Temporary addon" then browse to the firefox folder and select manifest.json.
Think you could help debug, test and package, a Safari extension, please feel free to fork this repository, Currently forked and rebuilt this for Chrome and Firefox using Ubuntu, unable to test for Safari.