Describe the bug
Unlike vanilla Anvils, the Anvil Upgrade can't accept certain Unicode characters, such as §, which is used for Minecraft's formatting codes (e.g., colored text).

To Reproduce
Steps to reproduce the behavior:

1. Open backpack
2. Add an Anvil Upgrade
3. Open the Anvil Upgrade's interface
4. Try to rename item with a formatting code included, such as §dObsidian Furnace.

Expected behavior
§ would be usable in the Anvil Upgrade interface, and display the formatting code's effect(s) on the text, just like a vanilla anvil.

Screenshots
What I'd expect to see:

Versions
Mod version - 3.20.11.1115

🤦 I'm silly – yeah. Anvils can do this on Bedrock without a mod. On JE, I'm able to do this because the modpack has Easy Anvils included. (Copy-pasting the text.)

Feel free to close if out-of-scope. :) I still believe it'd be nice to support, though at this point it's a feature request and not a bug report, ig!

How are you entering that character into Anvil? I can't use it there (tried copy pasting and it only pastes the "d" but not the formatting character) which makes me think it's some mod allowing that.

I will take a quick look at this and may add if super easy

So I took a look at this and the implementation is actually very involved where I don't see a good reason to add it to the mod - this would be used pretty rarely and player's can use vanilla anvil with Easy Anvil mod in those cases.