The new extensions model won't be added to Edge until after the browser debuts this summer as part of Windows 10, however.
Previously, Microsoft had announced that Edge would abandon much of the legacy support of Internet Explorer 11 (IE11) and talked about an alternate add-on model, which implied ActiveX would not be supported. It confirmed the move last week in a blog, adding Browser Helper Objects (BHO) to the now-gone list.
Both are crucial to IE's proprietary add-on and extension framework.
ActiveX controls were analogous to the add-ons other browser makers, notably Mozilla (Firefox) and Google (Chrome), later offered to extend the functionality of their applications. Meanwhile, BHOs were essentially plug-ins that also integrated with the browser. While BHOs became synonymous with browser toolbars over time, they also were used by the likes of Adobe, which built its IE in-browser PDF rendering plug-in using the technology.
ActiveX and BHOs are ancient, harking back to 1996 and 1997, respectively, and have a long history of security and abuse issues. Both are Windows-specific, and so have been relegated to second-class citizenship as a more open, standards-based Internet developed under the aegis of first Mozilla, then later Google and others.
"The need for ActiveX controls has been significantly reduced by HTML5-era capabilities, which also produces interoperable code across browsers," Microsoft noted on its new Edge development blog.
"This is another good example of how Microsoft has been disrupted by the fast-changing industry," said IDC analyst Al Gillen in a podcast recorded during Microsoft's Build developers conference two weeks ago. ActiveX, Gillen added, "locked IE into the past" because of its proprietary nature and early success, which Microsoft felt had to be supported with each new IE to please the mostly enterprise customers who relied on the technology.
Starting fresh with Edge -- which will replace IE as the default browser in Windows 10 -- lets Microsoft shed that legacy support and move to a cross-platform model, Gillen added.
The withdrawal of ActiveX, BHOs and other old technologies from Edge got scattered applause from the developers during a session at Microsoft's Build conference. But Sean Lyndersay, a principal program manager lead on Edge, said to those cheering, "You must not work in IT."
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