[fehmer]

Summary

  updateColors: {
    type: "checkbox",
+   initVal: false,
    label: "Update custom theme to current colors",
  },

A checkbox with no initVal is seeded undefined by SimpleModal. The required z.boolean() schema rejects undefined on submit, so renaming a custom theme without ticking the color-update checkbox was blocked ("Please fill in all fields"). Seed false (same convention as the DevOptions generate-data modal) so the field is a real boolean from birth.

Evidence

• Before (browser, dev server): rename a custom theme, checkbox left untouched → update blocked: "Please fill in all fields", modal stays open, name unchanged
  After (browser, dev server): same action → modal closes, "Updated" notification, name persisted; checked-box path also verified. No new console errors
• z.boolean().safeParse(undefined) → success: false vs safeParse(false) → success: true (the value the untouched field now holds)
• oxlint --format agent on Theme.tsx — clean
• oxlint --type-aware --type-check — one pre-existing finding in vitest.config.ts, untouched here
• oxfmt --check — clean

Merge Danger

Door: two-way

One-line form seed, no schema change, no persisted data. Revert restores the old block.

Blast Radius: minimal

Only the "Update custom theme" modal. The checkbox renders unchecked exactly as before; checked/unchecked values are unchanged.

Closes #8527

[fehmer]

Browser check on the dev server (account: quick-login user_131):

Before (parent commit, no initVal): update modal with the checkbox left untouched — the update is blocked and the theme is never renamed.

After (this PR): the same rename lands — modal closes, "Updated" notification, name persists; checked-box path verified too. Restored the theme to its original name afterwards.