Firefox is making major changes to extensions. (See the Mozilla blog.) By the end of 2017 the legacy extension APIs used by the HDL Extension for Firefox will no longer be supported. Testing indicates that the extension will no longer work as of Firefox 53, scheduled for release in April 2017.
Users who find the HDL Extension for Firefox indispensable could consider using the Firefox Extended Support Release, version 52, and are encouraged to contact firstname.lastname@example.org to inform us of the features of the extension that they find useful to include, should a rewrite of the software be undertaken in future.
CNRI Handle Extension for Firefox embeds a handle/DOI name resolver in the browser. It finds handles and DOI names used as references in web pages, in a variety of formats, resolves them via the Handle System, and gets back current information about the identified entity, e.g., current location. The results of that handle resolution are used to determine browser behavior, e.g., display the current version of a document even if it has been moved since the creation of the reference.
After installing this extension in your Firefox browser, you will be able to directly access handle URIs like
or Digital Object Identifier URIs like
by typing them into the address bar, clicking on links with such references, or even having one as the source of an image.
Your browser will resolve these handles using the Handle System. What's more, if you do follow a link to a web-to-handle proxy server (e.g., http://hdl.handle.net/4263537/4000 or http://dx.doi.org/10.1000/1), your browser will recognize this as a handle resolution and (configurably) offer additional services via a notification bar.
A configuration option can turn off redirecting to URLs embedded in the handle values, allowing you to examine the structure of the handle record.