After deploying a new version of a website the browser loads everything from its cache from the old webpage until a force refresh is done. Images are old, cookies are old, and s
You can append a variable to the end of each of your resources that changes with each deploy. For example you can name your stylesheets:
styles.css?id=1
with the id changing each time.
This will force the browser to download the new version as it cannot find it in its cache.