Firefox Nightly features a new internal Web Compatibility page that lists Firefox compatibility modifications for Internet sites and services.
While it is usually in the best interest of webmasters and companies to make sure that their sites display and work fine in all popular web browsers, it sometimes is not the case.
Web developers may test a site only in Chrome, the dominating browser when it comes to marketshare, or implement functionality that is only supported by certain browsers.
Browser makers like Mozilla face a tough decision when they notice that certain sites or services don't work properly in their browsers. While they could ignore incompatible sites, especially if a site uses non-standard technologies, it would fall back to the browser if users of it could not access a site or use certain features.
Making sites compatible in the browser, on the other hand, might send the wrong signal. While that is better from a user perspective, more and more sites might ignore all but the most popular browsers.
To make compatibility changes transparent, Mozilla added a new web compatibility page to Firefox (only Nightly for now) as a new about page in Firefox.
You may load the page by pointing Firefox to about:compat. Just type about:compat in the Firefox address bar to display all web compatibility modifications that are active at the time.
Mozilla divides the modifications into user agent overrides and interventions. User Agent overrides change the user agent of Firefox when connections to certain sites are made. Some sites may use the user agent of connecting browsers to block access completely, display a different design, or provide different functionality.
While that is justified sometimes, e.g. when a browser does not support a feature used by the site, it is sometimes used to exclude browsers for other reasons, e.g. because functionality was not tested in certain browsers.
Interventions, on the other hand, are deeper modifications to make sites compatible. Firefox may modify certain code used on these sites to enforce compatibility.
Each compatibility modification links to the bug on Bugzilla@Mozilla; click on the link to look up information about the underlying issue.
You may disable modifications with a click on the disable button next to them. The button toggles between disable and enable, so that you may enable the compatibility modification again at a later point in time.
Firefox's new about:compat page is a useful addition to Firefox that improves transparency when it comes to compatibility modifications made by Firefox. (via Sören)
Mozilla has not revealed a target for the inclusion in stable versions of the web browser.
Now You: Did you run into compatibility issues recently on the Web?Advertisement
Ghacks is a technology news blog that was founded in 2005 by Martin Brinkmann. It has since then become one of the most popular tech news sites on the Internet with five authors and regular contributions from freelance writers.