Generate TimezoneSelect options

[laurakwhit]

Description & motivation 💭

Generates options for the <TimezoneSelect /> instead of using a statically generated list which isn’t accurate half the year (e.g. with daylight savings and zones switching from PDT to PST).

E.g. if a user has "Pacific Daylight Time" saved in local storage, but zones now exist in "Pacific Standard Time" it will default to "Pacific Daylight Time" or, if that option doesn't exist, it will default back to the "local" option.

Screenshots (if applicable) 📸

Design Considerations 🎨

Testing 🧪

How was this tested 👻

• Manual testing
• E2E tests added
• Unit tests added

Steps for others to test: 🚶🏽‍♂️🚶🏽‍♀️

Checklists

Draft Checklist

Merge Checklist

Issue(s) closed

DT-3305

Docs

Any docs updates needed?

[vercel]

The latest updates on your projects. Learn more about Vercel for GitHub.

Project	Deployment	Review	Updated (UTC)
holocene	Ready	Preview, Comment	Dec 22, 2025 3:41pm

[temporal-cicd]

• ⚠️ Could not find a declaration file for module 'date-fns-tz'. '/home/runner/work/ui/ui/node_modules/.pnpm/date-fns-tz@1.3.8_date-fns@2.30.0/node_modules/date-fns-tz/index.js' implicitly has an 'any' type.

[temporal-cicd]

Warnings

⚠️

📊 Strict Mode: 10 errors in 4 files (0.8% of 1311 total) src/lib/stores/time-format.ts (1) L2:24: Could not find a declaration file for module 'date-fns-tz'. '/home/runner/work/ui/ui/node_modules/.pnpm/date-fns-tz@1.3.8_date-fns@2.30.0/node_modules/date-fns-tz/index.js' implicitly has an 'any' type. src/lib/utilities/format-date.ts (1) L121:3: Function lacks ending return statement and return type does not include 'undefined'. src/lib/components/timezone-select.svelte (1) L142:13: Type 'boolean | null' is not assignable to type 'boolean | undefined'. src/lib/components/workflow/workflow-filters.svelte (7) L95:6: Type 'string | null' is not assignable to type 'string | undefined'. L103:11: Type '{ icon: "search"; type: "search"; id: string; placeholder: string; label: string; labelHidden: true; value: string | undefined; }' is not assignable to type '__sveltets_2_PropsWithChildren<$$Props, { 'before-input': { disabled: boolean; }; 'after-input': { disabled: boolean; }; }> | undefined'. L113:11: Type '{ icon: "search"; type: "search"; id: string; placeholder: string; label: string; labelHidden: true; value: string | undefined; }' is not assignable to type '__sveltets_2_PropsWithChildren<$$Props, { 'before-input': { disabled: boolean; }; 'after-input': { disabled: boolean; }; }> | undefined'. L129:16: Type 'null' is not assignable to type 'SelectOptionValue'. L140:13: Type 'WorkflowStatus | undefined' is not assignable to type 'SelectOptionValue'. L144:19: Type 'string | null' is not assignable to type 'SelectOptionValue'. L149:13: Type 'string | null' is not assignable to type 'SelectOptionValue'.

Generated by 🚫 dangerJS against c000061