All documents, drawings, and new markups (markups created after the release) will be compatible with both versions of the Brava Viewer. This means that any user will be able to view and mark up documents regardless of the browser they are using. If you create new markups using HTML5, you will be able to view and edit those markups using ActiveX (and vice versa).
Any markups created before the release, including those created in Flash, will also be compatible with both versions of the Brava Viewer. The version of the Viewer that opens when you access the View and Markup tool will depend on your browser and on your Brava_Default setting (specified in User Settings).