When configuring a ListView with a click action, the tab-index value is set to 0, whereas it defaults to -1 when no click action is set. However, when configuring a Gallery widget without a click action, the widget items are assigned a default tab-index value of 0. This is undesirable because keyboard users can select a widget item without an associated click action. Ideally, the tab-index attribute should only be set if a click action is configured, or the tab-index should be set to -1 when no click action is assigned.
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