How to configure the server to use the site while the file is uploading?

Question

PHP

The web server is nginx. The file generates and gives php. In the browser.
File generation takes a long time. What needs to be configured so that while the file is being generated (php is working), you can open a new tab in the browser and open another address of the same site? Now the new tab is loaded only after php returns the response in the previous tab.

Answer 1

Maybe it's worth looking towards ajax, maybe it will help solve the problem. Although the issue is not well understood.