some extensions allow you to hook into browser chrome.
while the actual work of the extension may be done in a web app, extensions get more access to the interface of a browser than a normal web app
example: the Buffer extension could probably just be a button that simply loads a JS file from their servers that does all the real work. WIthout being an extension, you wouldn't have the convenience of having the button on every page you view.
while the actual work of the extension may be done in a web app, extensions get more access to the interface of a browser than a normal web app
example: the Buffer extension could probably just be a button that simply loads a JS file from their servers that does all the real work. WIthout being an extension, you wouldn't have the convenience of having the button on every page you view.