Problem

The date picker field in JSM Forms on the customer portal renders in US format (MM/DD/YYYY, week starting Sunday) despite the locale being correctly set to en_GB across all relevant settings. The analytics payload confirms locale: "en_GB" is being transmitted to the frontend, but the ProForma Forms date picker component does not apply it.

Environment

• Jira Service Management Cloud
• ProForma/JSM Forms date field on customer portal

Steps to Reproduce

1. Set Atlassian account language to English (United Kingdom) and timezone to (GMT+00:00) London
2. Set browser language to English (United Kingdom)
3. In a JSM project, go to Project Settings → Language support and set default language to English (United Kingdom)
4. Go to Project Settings → Forms and create a form with a Date field
5. Link the form to a request type
6. Navigate to the customer portal and open the request type
7. Click on the date field in the form

Expected Results

• Date picker displays in DD/MM/YYYY format (UK standard)
• Calendar week starts on Monday

Actual Results

• Date picker displays in MM/DD/YYYY format (US standard)
• Calendar week starts on Sunday
• Dev tools confirm locale: "en_GB" is correctly sent in the analytics payload but not respected by the date picker component

Workaround

(Add a workaround, if available)

Notes