This plugin synchronizes a:visited links across devices
LinkSync synchronizes visited links, and shows this as a red link on other devices.
All data is 1-way encrypted (hashed) by the client, so this plugin is very secure.
Check the options page to choose colors.
Q: Why doesn't this plugin work on google.com?
A: Turn off Google Instant in the search settings
Q: Why doesn't this plugin work on a few links?
A: Some links are redirects, only the page you land at is stored. So if a link leads to m.google.com and you get redirected to google.com, only google.com is stored in the history.