On the theme of productivity and effiecency... I´d like to share the extensions I use daily to get more productive and do less stuff, while achieving even more.
Most extensions that I´ve installed tend to fade away and never gets used. These are the grain of gold of browser extensions for programmers that has stayed with me.
Whenever doing an AJAX call or browsing an API through HTTP GET´s in the browser JSONView really comes in handy, formatting and making json more readable in the browser.
Easily style any site the way you want and persist that style. Sort of like Greasemonkey/Userscripts (which works out of the box in Chrome), but for CSS. Create and manage CSS rules for matching URLs. Useful when performing repetetive tasks without scripting on a site. Removing noisy elements on sites that is used often, or trying out (persistant) styles on a project of yours, without deploying any code.
This is not just an extension, but also a great app for storing and managing passwords securely. It is a paid app and browser extension that comes to handy whenever i use a browser. I´ve used 1Password since their launch, but mostly since they launched the Chrome extension. This is not solely aimed at programmers of course, but a must have for security reasons for everyone.
Being a bit of a geek when it comes to IDE´s/Text Editors, VIM is and has been my first choice the last couple of years. Since faster navigation is one of the pros using VIM, the same keystrokes and navigation methods can be applied in the browser. The usual HJKL is implemented as well as Insert mode and find. Give VIMium a go!
I´ve only touched on the surface of browser extensions for Web Developers. The less extensions I´m dependent on, the more I can focus on stuff that matters. It tends to be the same for me when it comes to programming or developing products.
However, those few golden grains in your toolbox can be hugely valuable and stay with you forever. So, please tell me which extensions I´m missing here.