overlayOptions.appendTo Not Respected in PrimeNG v21 (Overlay-Based Components)

[O2sa]

After upgrading to PrimeNG v21, passing appendTo through overlayOptions in overlay-based components (such as Select, MultiSelect, Menu, DatePicker, etc.) no longer works as expected.

This behavior was working correctly in previous versions.

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Expected Behavior

When setting:

<p-select
  [overlayOptions]="{ appendTo: 'body' }">
</p-select>

The appendTo value inside overlayOptions should be forwarded to the internal <p-overlay> component and applied correctly.

The same expectation applies when overlayOptions.appendTo is provided via global configuration.

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Actual Behavior in v21

The appendTo value passed via:

• overlayOptions input
• Global configuration (overlayOptions)

is ignored.

Instead, the final appendTo value appears to be resolved only from:

1. The direct @Input() appendTo of the component (e.g., Select)
2. The appendTo value coming from the base component/global config

As a result, overlayOptions.appendTo has no effect.

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Investigation / Root Cause

After reviewing the source code:

• Overlay-based components (e.g., Select, MultiSelect) extend a base component.

• The base component provides configuration values (including appendTo) via global config.

• Inside these components, appendTo is computed using:

  • The direct appendTo input
  • The inherited/base config value

• However:

  • overlayOptions.appendTo from the component input is not included in the resolution logic.
  • overlayOptions.appendTo from global config is also not included.

This leads to inconsistency because:

• overlayOptions is exposed as a supported API.
• But appendTo inside it is not respected during the final value calculation.

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Current Status

A PR primefaces/primeng#19388 has already been opened to address this issue for:

• Select
• MultiSelect

However, since many other components internally use Overlay, it is unclear:

• Whether this issue affects all overlay-based components.
• Whether the current behavior is intentional in v21.
• What the intended resolution priority for appendTo should be.

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Questions

1. Is ignoring overlayOptions.appendTo intentional in v21?

2. What is the intended priority order for resolving appendTo?

   • Direct appendTo input?
   • overlayOptions.appendTo?
   • Global config appendTo?
   • Global config overlayOptions.appendTo?

3. Should all overlay-based components follow a unified resolution strategy?

4. Would it be better to centralize appendTo resolution logic inside the Overlay component to avoid duplication and inconsistencies?