7Cav Zulu Conversion от Dave Raynor

This extension appends a conversion to your local timezone after any zulu times displayed on 7cav.us. It supports all common formatting for the time: with or without a colon or space, Z or Zulu.

For example:
0800Z

Becomes:
0800Z (0200CST)

Your timezone is detected using your system timezone, and the timezone abbreviation is set in the extension options.

It will only access 7cav.us, not every webpage you visit.