f3 screen doesn't work properly when you're above y:256 (cant check day)

Thank you for your report!
However, this issue is Invalid.

Your game, launcher or server is modified.
If you can reproduce the issue in a vanilla environment, please recreate the issue.

• Any non-standard client/server/launcher build needs to be taken up with the appropriate team, not Mojang.

• Any plugin issues need to be addressed to the creator of the plugin or resource pack.

• If you have problems on large servers, such as The Hive and Hypixel, please contact them first as they run modified server software.

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This appears to also impact vanilla, but, the issue still is invalid.

You have posted a feature request or a suggestion. This site is for bug reports only.
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I'm not aware of a technical reason for not including the day in F3 (unlike biome, which does require an in-bounds y value), but the bug tracker still isn't the appropriate venue for this.

Quick Links:
📓 Bug Tracker Guidelines – 💬 Community Support – 📧 Mojang Support
📓 Project Summary – ✍️ Feedback and Suggestions – 📖 Game Wiki