Gorgeous tool, but this is what happens when you marry Microsoft:

Browsers: DRA is built on Silverlight which uses the old plugin API (NPAPI), which many browsers have stopped supporting.

• IE: Works.
• Safari: It did work on Yosemite (MacOS 10.8), but on Sierra (10.12) it does not function correctly. I don’t know about other versions.(Safari/Preferences/Security/Plugin Settings).
• Firefox ESR: Works. Tools/Addons will take you to the page to manage Addons, including plugins. There you can allow or disallow each plugin (or set it to ask each time). Note: On Mac Sierra, Silverlight runs much slower than before.
• Chrome: Does not work.
• Standard Firefox version 52 and above: Does not work.
• Edge: Does not work.

DRA 2.2 depends on a Bing Maps control that is no longer officially supported, as of November 30th. But it still works and I recommend continuing to use it. From what I can glean, it could continue to work for a while, but there’s no guarantee now that the control is unsupported. Maps saved in 2.2 can be loaded in 2.5.

The new version, DRA 2.5 does not depend on the Bing Maps control, so should continue to work for the foreseeable future. The main features and data remain, although Alaska does not work correctly. A link and details on what features are still supported are below.

Source: Dave’s Redistricting