With ID 18.5 UXP plugin support will be available for the first time to all InDesign users: Learn about new features and enhancements in Adobe InDesign 18.5.
The phased rollout started this week (more on this in the InDesign Prerelease Program)
Can’t wait for that update to show up in my CCD 
InDesign v18.5 is now available. Please go to Help → Check for updates in Creative Cloud Desktop to get the latest version.