This repo demonstrates inconsistencies between ISR using NextJS 14 and NextJS 15.

This repo uses NextJS 15 with React 19.0.0-rc-02c0e824-20241028. See https://github.com/samstr/isr-demo-nextjs14 for the NextJS 14 comparison.

Steps to reproduce

1. npm install
2. npm run build
3. npm start
4. Go to http://localhost:3000 and click the example links

Expected behavior

ISR should work correctly. The random number should be cached for 10 seconds as you refresh the page.

Actual behavior

The number does not get cached. It changes on every refresh.