[BUG] Trezu - Settings: Time zone field displays empty value by default

[rknearn-qa]

Summary

In Settings → Preferences, the Time zone field displays an empty value for users who have not previously configured their time zone. Instead of showing a default or detected value, the field appears blank, creating ambiguity regarding the current system configuration.

Preconditions:

• User has not changed the time zone previously
• Treasury settings page is accessible https://trezu.app/one-more-zero-balance-treasury.sputnik-dao.near/settings

Steps To Reproduce

1. Open the specified treasury Settings page
2. Navigate to Preferences
3. Observe the Time zone field value

Actual Result:

• Time zone field displays an empty
• No default, placeholder, or detected time zone is shown

Expected Result:

• Time zone field should display:

  • Either a system-detected default time zone (e.g., based on browser locale)
  • OR a clearly defined default value (e.g., UTC)
  • OR a visible placeholder indicating selection is required

Special Notes:

Possible Root Cause:

* Missing default initialization for the time zone setting in user preferences
* Backend returns `null` / empty value and frontend does not apply fallback logic
* Controlled component may not handle undefined state correctly

Workarounds:

• Manually select and save a time zone

Repro Rate:

Always

Setup - OS - Browser - Environment

• OS / Devices: Windows 11 (x64), Motorola G23 (Android 14), Iphone XR (iOs)
• Screen resolution(s): 1366 x 768, 1600 x 720, 1792×828
• Browser(s) + version(s): Chrome (144.0.7559.97), Mozilla Firefox (147.0.2), Brave (1.86.148)
• Wallet: Meteor
• App environment: Staging (trezu.app)
• Near Network: Mainnet

Resources & Additional Notes

Impact:

User Impact:

• Users may be unsure which time zone is currently applied
• Potential confusion regarding time-based operations (deadlines, timestamps)

System Impact:

• Inconsistent preference state initialization
• Potential misinterpretation of scheduling-related features

Business / Release Risk:

• Minor UX issue but may affect user trust in time-sensitive treasury actions

QA Verdict:

Rationale:

• Settings should never present undefined or ambiguous configuration states
• Clear defaults are required for predictable user experience

Recommendation:

• Implement fallback default (browser-detected or UTC)
• Ensure backend returns explicit default value instead of null
• Add regression test for first-time preference initialization

Priority

🟡 P2 : Medium