`isDefaultValue` not updating when changing date field

[marc-niclas]

Describe the bug

On changing a date field, it seems tanstack is not changing isDefaultValue to false, as I would expect.

Your minimal, reproducible example

https://stackblitz.com/edit/vitejs-vite-sobdcz8j?file=src%2FApp.tsx

Steps to reproduce

1. Change the date
2. Observe equality check is false and isPristine is false
3. isDefaultValue is still true
4. Changing the text field however does change isDefaultValue to false

Expected behavior

Changing a date field should change isDefaultValue to false

How often does this bug happen?

Every time

Screenshots or Videos

Platform

• macOS 15.5
• chrome/brave

TanStack Form adapter

None

TanStack Form version

1.19.2

TypeScript version

No response

Additional context

No response

[LeCarbonator]

Related to #1628