Potential bug where data in custom fields is cleared if certain fields change

zogstrip · August 14, 2026, 11:20am

Thanks for the report, it’ll be fixed by

github.com/discourse/discourse

FIX: Stop the event builder from clearing typed custom fields (#42624)

main ← event-builder-custom-fields

merged 12:44PM - 14 Aug 26 UTC

ZogStriP

+112 -4

Previously, values typed into the event builder's custom fields were cleared as …soon as another field changed (location, image, name, …), and toggling between the compact and advanced screens could permanently revert them to stale values. This change commits custom field values through the form's `set` (a field's `@onSet` replaces FormKit's default write, so skipping it left the typed value out of the form data), replaces the `customFields` reference on every write (mutating inside the object never invalidated `compactInitialState`, so the compact screen served stale values back), and tracks `formData` (untracked, the advanced screen always reinitialized from the modal's construction-time snapshot). Reported in https://meta.discourse.org/t/potential-bug-where-data-in-custom-fields-is-cleared-if-certain-fields-change/410050

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Potential bug where data in custom fields is cleared if certain fields change

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