The bug
Unlike regular coordinates, relative and local coordinates don't require a space after the tilde/caret/number.
How to reproduce
Type
/summon cow ~ 10~
→❌ A cow is summoned at Y=10
Expected behavior
Syntax error; ~ 10 ~ should be used
Comments 2
For now this is working as intended.
We're already working on achieving parity across versions where possible, and we're very keen to hear your requests or suggestions, so we'd encourage you to make a post at https://feedback.minecraft.net, or upvote an existing topic there.
Quick Links:
📓 Issue Guidelines – 💬 Mojang Support – 📧 Suggestions – 📖 Minecraft Wiki
The /summon cow ~3 is intended.
Since x,y,z.