In Dragonflight's most recent patch update, there was a change with the addon API, restricting the Distance Checking functionality. Blizzard has clarified that this change won't be coming to WoW Classic or Wrath Classic at this time, but might potentially be included next year in future updates.
Greetings,Just for clarification, we don’t plan to make this API adjustment to Classic Era or Wrath Classic at this time. We will be reviewing this adjustment for potential inclusion in our next Era Patch (1.15.1) and Wrath/Cata Classic (4.4.0) which will both arrive sometime next year, but we don’t intend to pick up this adjustment at this time. This isn’t something we’d want to pick up mid-raid tier while guilds are progressing in ICC.Thank you!
It never stopped working. However, it is entirely up to addon authors if they want to pre-emptively remove support for this in classic or not on the assumption that we may, at some point, change this.
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