This issue is a known rendering bug in Data Grid 2 (especially when using multi-select dropdown filters with large page sizes). It happens when the user makes quick successive selections — the widget re-renders before the previous request finishes, causing a “Could not render widget…” error.
Workarounds
Reduce page size (e.g., from 100 → 20 or 50) – lowers render load.
Debounce the filter – avoid rapid re-renders by letting each filter action finish before the next (custom JS or wait for official fix).
Upgrade widgets – make sure you’re using the latest version of Data Grid 2 and Dropdown Filter in Marketplace. Several releases after Mendix 10.22 fixed partial render issues.
Avoid multi-select filters with large datasets – use reference selectors or pop-up filters instead.
Why it happens
Each multi-select change triggers a full grid reload.
With a high page size, multiple async fetches overlap.
The widget fails to mount properly before the previous DOM update completes.
If updating to the latest widget version (and clearing cache) doesn’t fix it, raise a ticket with Mendix Support including:
Mendix version, widget version, and browser console logs.