Describe the bug

I recently tried updating our app to the latest version of Svelte, and noticed that our formatted inputs no longer work for Firefox users.

The inputs work as expected through Svelte 5.35.7, but starting in Svelte 5.36.0 what is displayed in the input no longer matches the bound Svelte state.

Are we doing something wrong here? If there isn't a simple workaround this blocks us from upgrading Svelte.

Reproduction

https://svelte.dev/playground/bf28bf223e4746a199f15ca80385487d?version=5.38.0

Last version that worked: https://svelte.dev/playground/bf28bf223e4746a199f15ca80385487d?version=5.35.7

Logs

System Info

Windows 11, Firefox 141

Severity

blocking an upgrade