In this documentation, we can check how to display out of stock products in Magento.
1) Login to Magento admin panel.
2) Go to ‘System’.
3) Click the option ‘Configuration’.
4) Go to Catalog >> Inventory.
5) Select the option ‘Stock Options’.
6) Change the ‘Display Out of Stock Products’ to ‘Yes’.
7) Click the button ‘Save Config’.
That is how we can display out of stock products in Magento.
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