Hello @Werner Noske. Now that VS Code has replaced Atelier as our cross-platform IDE (Studio is still supported), we have removed the plugin from the Eclipse Marketplace. The page you reference will soon make this clear as well. As @Dmitry Maslennikov says, we encourage developers to follow the guidance in this announcement and move to the VS Code platform if at all possible. Thanks!

Hi @Sam Duncan. This answer should solve your problem: https://community.intersystems.com/post/vscode-missing-iris-icon-activity-bar