Compatibility/UA Override & Interventions Testing
Mozilla added a new web compatibility page to Firefox as a new about page in Firefox, in order to make compatibility modifications for Internet sites and services transparent.
These modifications are divided into User Agent Overrides and Interventions:
- Interventions - 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.
- User Agent Override - 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.
Viewing the list of Interventions and Overrides on Desktop and Mobile
Verifying if the website has been fixed on their end
- 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. - 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.
What you need:
- Windows machine - MacOS machine - Linux machine - Mobile device running Android