To add a Tabs block, click the Toggle block inserter ( + ) in the top left corner of the Gutenberg editor and select Tabs.
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A preview of two Tabs should appear where you can add the content.
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Changing the Tab Label
To change the Tab Label, open up the Document Overview located on the top left.
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Expand the Tab Block and select the Tab Item you want to change.
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On the Right Sidebar, under Tab Settings, you’ll find a field for the Tab Label
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Adding additional Tabs
To add additional Tabs, make sure the Tabs block is selected in the Document Overview.
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You will see a ( + ) button appear below your Tabs block.
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Click the ( + ) button and a new Tab will be created.
Adding content to a Tab
To add content, simply click to type within either the Tab title or description. Navigate to other Tabs by clicking on the Tab you intend to add content to.