“React useEffect not working on page refresh” is a common issue that occurs when working with React, a JavaScript library for building user interfaces. The useEffect hook is a built-in React hook that allows you to synchronize a component with an external system, such as a backend API or browser storage. When a component using the useEffect hook is rendered, React will run the effect function and clean it up on the next render.

The issue of the useEffect hook not working on page refresh can occur for several reasons, some of which include:

1. Incorrect dependencies: The useEffect hook accepts an array of dependencies as its second argument. If the dependencies are not correctly specified, the effect function may not be run on page refresh.
2. Missing dependency on location: If your component is using the useEffect hook to synchronize with the browser’s location, you’ll need to include it as a dependency.
3. Incorrect cleanup logic: The useEffect hook’s cleanup function is responsible for cleaning up any side-effects that were set up in the effect function. If the cleanup logic is incorrect, it can prevent the effect function from being re-run on page refresh.
4. Server-side rendering: If your React application is server-rendered, the useEffect hook will not be run on the initial render because React has already generated the HTML on the server. You would need to run the same logic on the client-side.

To fix the issue, you’ll need to ensure that your component’s dependencies are correctly specified, and that any necessary dependencies, such as location, are included. You should also verify that the cleanup logic is correct, and if your application is server-rendered, make sure that the same logic is run on the client-side after the initial render.

In addition, it can be beneficial to use tools like the React Developer Tools extension to inspect the component state and props, and ensure that the component is re-rendering correctly. If necessary, you can also add console.log statements to trace the flow of your component and see when the effect function is being run.