ICMIZER works from any modern browser
https://www.icmpoker.com/icmizer/
If you don't want to work with ICMIZER from the browser, you can download a desktop client.
Downloadable version for Windows
You can download ICMIZER for Windows here:
https://www.icmpoker.com/en/download/
Downloadable version for macOS
You can also download ICMIZER installer for Mac from here:
https://www.icmpoker.com/en/download/