you gotta upload the texture yourself, not sure why but thats how it works
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It should work both in-studio and in-game as EditableImage is now released. However, roblox updated how using roblox texture assets for editableImage works. You can no longer use public assets. You have to own the texture, and also there are new rate limits, so overall, the texture feature right now is no where near as nice as it used to be, so use this feature sparingly.