Date binding misbehaves (probably depending on locale)

[tosinek]

Describe the bug

Date binding input type=date bind:value={date} is broken if system locale (at least on Windows) is not set to MM/DD/YY (so it is broken for DD/MM/YY or YY/MM/DD), especially when editing an existing date.

I tested Chrome, Edge and Firefox.

Using on:input={e => date=e} or on:change will not work either.

Reproduction

With locale DD/MM/YYYY, the most annoying case is when you type "0" (for 01) in days or months, it resets the whole field (if there is an existing date already).

REPL with examples:
https://svelte.dev/repl/594639752b464fdc8ad7cc2d50f3d499?version=4.2.8

Logs

No particular logs, in some cases I was able to make it log

The specified value "[object Event]" does not conform to the required format, "yyyy-MM-dd".
prop_dev	@	VM233:350
update	@	VM233:426
update	@	VM233:177
flush	@	VM233:144
Promise.then (async)		
schedule_update	@	VM233:109
make_dirty	@	VM233:222
eval	@	VM233:260
change_handler	@	VM233:472

System Info

Windows 11, regional settings set to Czech. Newest Chrome and Firefox. Newest Svelte (from 3.55.1 up to 4.2.8)

Severity

annoyance

Workaround

As a workaround, use two variables instead of one.

<input type=date value={initialDate} on:change={handleDateChange}>

let otherDate
const handleDateChange = () => {
    otherDate = event.target.value
}

[tosinek]

Can you please confirm this bug? (@Conduitry, I found you added such label to one of the issues). The latest repl:
https://svelte.dev/repl/594639752b464fdc8ad7cc2d50f3d499?version=4.2.8