Date field value resets when pressing "save".

[baalej]

Description

When I try to edit a field of type date that it already had a value asigned it resets to that value whenever I press "save".

start:
  type: date
  display: D MMMM YYYY
  time: true
end:
  type: date
  display: D MMMM YYYY
  default: now

Expected behavior
It should keep the edited value, and store it on "save".

Screenshots

To reproduce

1. Go to an already created page with a field date that already contains a value
2. Edit that field
3. Press save
4. The date will be reset to the one before you edited

Your setup

"getkirby/cms": "^5.2"

Console output

Your system (please complete the following information)

• Device: Macbook Pro M3 Pro
• OS: MacOs 15.7.3
• Browser: Firefox
• Version: 148.0.2

Gravacio.de.pantalla.2026-03-16.a.les.9.48.43.mov

[afbora]

I can reproduce the the issue 5.0.0+ and even on 4.8.0 (not tested more old versions). I'll keep digging to find source of the issue.

[afbora]

I tested this a bit more and it doesn’t seem to be only related to save. It looks more related to the display format.

Formats that seem to work:

• YYYY-MM-DD
• DD.MM.YYYY

Formats that seem problematic:

• D MMMM YYYY
• D MMM YYYY
• MMMM YYYY

Because of that, I think this may not be just a general save regression, but something related to the display/parse side.

Possible solution

Not sure but a possible fix could be to make the date input try parsing with the active display format first and only fall back to the generic parser afterwards. That would make formatting and parsing more consistent, especially for text-based month formats.