Occasionally I load a web page which contains a text line and immediately appended after the right side an image <img>
I want to let the <img> start in a next line.
So I need a kind of <br> separation between text and image (not with <P>).
However I have no access to the original webserver but want to apply a modification afterwards (after loading)
I can imagine that there is a CSS property (for <img>) which let me tell the browser engine "put in next line".
How can I achieve this in detail?