[2] ActiveX is still supported in the "Internet Explorer mode" of Microsoft Edge (which has a different, incompatible extension system, as it is based on Google's Chromium project).

[5] ActiveX is supported in many rapid application development technologies, such as Active Template Library, Delphi, JavaBeans, Microsoft Foundation Class Library, Qt, Visual Basic, Windows Forms and wxWidgets, to enable application developers to embed ActiveX controls into their products.

Faced with the complexity of OLE 2.0 and with poor support for COM in MFC, Microsoft simplified the specification and rebranded the technology as ActiveX in 1996.

In response to this complexity, Microsoft produced wizards, ATL base classes, macros and C++ language extensions to make it simpler to write controls.

[10] The ActiveX security model relied almost entirely on identifying trusted component developers using a code signing technology called Authenticode.

[16] While Microsoft made significant efforts to push the cross-platform aspect of ActiveX by way of publishing the API, ultimately the cross-platform effort failed due to the ActiveX controls being written in C or C++ and being compiled in Intel x86 Assembly language, making them executable only on Windows machines where they can call the standard Win32 APIs.