Deprecated Default Values Without Square Brackets for Array, Set, and List Attributes

Setting a default value without square brackets is deprecated and can lead to unexpected behavior. To set a default value for these attribute types, surround comma-separated values with []; for example, default="['red', 'green', 'blue']".

Where: This change applies to orgs with Lightning components in Lightning Experience, Salesforce Classic, and all versions of the Salesforce app.

How: Here’s an example of attributes for an array, a list, and a set.

<aura:attribute name="colorArray" type="String[]" default="['red', 'green', 'blue']" />
<aura:attribute name="colorList" type="List" default="['red', 'green', 'blue']" />
<aura:attribute name="colorSet" type="Set" default="['red', 'green', 'blue']" />