Using Background Utility Items

Implement the lightning:backgroundUtilityItem interface to create a component that fires and responds to events without rendering in the utility bar.

Lightning Web Components (LWC) doesn’t currently support working with background utility items.

Note

This component implements lightning:backgroundUtilityItem and listens for lightning:tabCreated events when the app loads. The component prevents more than 5 tabs from opening.
<aura:component implements="lightning:backgroundUtilityItem">
    <aura:attribute name="limit" default="5" type="Integer" />
    <aura:handler event="lightning:tabCreated" action="{!c.onTabCreated}" />
    <lightning:workspaceAPI aura:id="workspace" />
</aura:component>
When a tab is created, the event handler calls onTabCreated in the component’s controller and checks how many tabs are open. If the number of tabs is more than 5, the leftmost tab automatically closes.
({
    onTabCreated: function(cmp) {
        var workspace = cmp.find("workspace");
        var limit = cmp.get("v.limit");
        workspace.getAllTabInfo().then(function (tabInfo) {
            if (tabInfo.length > limit) {
                workspace.closeTab({
                    tabId: tabInfo[0].tabId
                });
            }
        });
    }
})

Background utility items are added to an app the same way normal utility items are, but they don’t appear in the utility bar. The Icon representing hidden status icon appears next to background utility items on the utility item list. If you have only background utility items in your utility bar, the utility bar doesn’t appear in your app. You need at least one non-background utility item in your utility bar for it to appear.