Detailed answer
The download attribute expresses an intent to download the destination and can suggest a filename.
Actual behavior depends on the origin, browser, and server headers. For files you control, configure the response appropriately and test it. Do not assume the attribute overrides any third-party server's behavior.
Example
<a href="/examples/hello.html" download="hello.html">Download HTML example</a>
Understanding the behavior
Download expresses an intention to save a resource and can suggest a filename. Browser behavior depends on the URL's origin, headers and other restrictions. It is not a way to force every third-party URL to download.
Practical implementation notes
Test the served file response and Content-Disposition when downloads matter. The linked asset should have an accurate type and a clear filename; a button-looking anchor cannot compensate for an HTML error page.
How to check it
Check resource origin and server response headers as well as the download attribute.
Expected result
You understand the browser's actual behavior rather than assuming universal support.
Watch out: A suggested filename and download behavior are not universal guarantees.
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