What carries over
Headings, paragraphs, bold, italic, underline and strikethrough, links, line breaks, numbered and bulleted lists, block quotes, preformatted code, tables with merged cells, horizontal rules and images. Colours, highlights, text alignment, font sizes and page breaks come across from inline styles and from simple style sheets in the page, such as rules for tags, classes and ids.
What does not
This is a document converter, not a full web browser. Scripts never run, and multi-column layouts, floats, positioned boxes and web fonts are left out, so the text flows in a single clean column with a built-in font. Pictures from the web are not downloaded; add them with Add images, or include them as data URLs.
Privacy
Your HTML is read and turned into a PDF by your browser. Nothing is uploaded, nothing on the page is fetched, and no script in your HTML is ever run.