Third-party apps can no longer open links from Edge in other browsers in Windows 11 test. Previously, these applications could bypass the Microsoft-edge:// protocol, which Windows automatically opens certain links in Edge browsers.
It is still unclear how exactly Microsoft will prevent the protocol circumventions in the Insider Preview build 22499. The maker of one such bypass app, EdgeDeflector, was the first to notice the news and says Microsoft has added about 8kB of extra code to the protocol. He calls Microsoft’s choice “anticompetitive.” According to him, it is possible to circumvent the restriction, but that requires “destructive changes” to be made to Windows. That’s why the maker says EdgeDeflector won’t update again until the restriction is rolled back.
Microsoft uses the Microsoft-edge:// protocol for various internal applications. For example, if users enter a term through the Windows search bar and click “Open in a browser” or click a help link in Windows settings, that protocol will automatically open the Edge browser, regardless of which browser is chosen as “default”. In Windows 11, users must set their default browser by extension, such as .pdf, .html, and https://, but the microsoft-edge:// protocol cannot be modified. Even if the Edge browser is uninstalled, the protocol will not switch to the default browser. Then only an error message will be displayed when it tries to open Edge.
For that reason, a number of third-party apps have been released over the years, such as EdgeDeflector and SearchDeflector, which allow users to choose a different browser where the protocol opens links. Brave has already implemented such a bypass feature in its browser. Firefox also recently said it will release a feature that will allow Microsoft-edge:// links to automatically redirect to that browser. However, Mozilla confirms to The Register that this function will no longer work in Firefox due to Microsoft’s step. It is not yet known when the Preview build will be available to all Windows users.