On Macs, Firefox has stopped supporting Silverlight in September (even on their 'extended support' ESR version). Unfortunately, the same does not apply to Apple computers. This is available on all current versions of Windows, and will remain available at least until the end of 2021. On Windows machines, Silverlight remains available through the Internet Explorer browser. In view of this, we are currently engaged in a rapid development effort to provide access to the EPPI-Reviewer 4 database through web pages – and not just the Silverlight plugin. Unfortunately, with the advent of mobile devices, Silverlight has become outdated, and new browsers – even on Windows and Macs – are no longer supporting this type of plugin. This has enabled us to provide a ‘desktop-like’ application experience in a web browser across the Windows and (Mac)OSX operating systems. EPPI-Reviewer version 4 runs in the Microsoft Silverlight browser plugin.