Why do support people suggest "clear browser cache"??

Question

Browsers

Hello!
Every trip to the support of something (ivi.ru, etc) ends with a suggestion to clear the browser cache.
Question: why? ;)
No, I basically understand that there is any static that the browser tries not to re-download in order to save traffic ... And if something fresh is put on the site, but it is not fresh in the browser, then there may be problems.
But the same is treated by pressing ctrl-f5 instead of f5.
(Probably).

Or I do not understand something, and the essence of the idea is different?
(Yes, I'm not a coder, alas).
And what can stick there in general, besides static?
And by what criteria does the browser decide that it's time to refresh the cache?
I know that HTTP allows you to specify what should be cached and for how long. So why do additional gestures from the browser?

Answer 1

Hey!
They ask you to clear the cache so that locally cached files are deleted and new updated files are downloaded instead.
Yes, you are right, the browser caches everything it can (images, css, js, html, media, etc.) locally for each user. Each file that the browser requests has its own cache time, each developer can set the cache lifetime to their liking.
What for? In order not to download the same files when reopening the browser, thereby saving traffic and increasing reload time.
The F5 button does not clear the cache, but only refreshes the page and pulls all the files from the cache and from the server.
Statistics uses cookies, local storage, etc. You can see what the browser saves in the F12 developer tools, application tab

On the next screen, the Network tab (network) here you can see all the downloaded files when you visit the page. The arrow shows the files that the browser displays from the cache, these files open instantly.

If you have the developer panel open, you can clear the cache using the refresh page button. Press and hold the button and you will have additional options for clearing the cache.

You can also disable the cache in the Network tab, it doesn't always work, but it does something