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LWCIntermediatecomboboxmodalcss

Debug lightning-combobox dropdown clipped inside modal overflow hidden

Real World Scenario

Filter combobox inside custom modal LWC shows dropdown clipped at modal boundary; users cannot select lower options.

Expected Answer

• Remove overflow:hidden on modal container or apply overflow:visible on combobox host section • Use lightning-modal base components following SLDS portal patterns where available • Dropdown may render in shadow DOM — parent overflow affects clipping • Alternative: replace combobox with searchable picklist pattern opening below fold • Test z-index stacking with other popovers on page • Mobile modal full-screen avoids clipping on small viewports • Document modal + overlay component pairing standards

Follow-Up Questions & Answers

Click to expand — each follow-up includes a direct, interview-ready answer

Direct answer: Remove overflow:hidden on modal container or apply overflow:visible on combobox host section Also consider: Use lightning-modal base components following SLDS portal patterns where available In practice: Dropdown may render in shadow DOM — parent overflow affects clipping Balance speed of delivery with maintainability.

Architect Perspective

Modal + overlay components are a common UX trap — standardize on platform modal patterns.