Exporting an HTML presentation to another format sounds simple: the slides look perfect in the browser, so the export should look the same. In practice, a handful of web techniques that work beautifully on screen can cause surprises during export. Knowing these pitfalls in advance saves time and frustration, whether you are exporting to PDF, images or PowerPoint.

1. Web fonts that load late

Many decks use custom fonts loaded from a font service or your own server. Browsers often display a fallback font first and swap in the custom one once it downloads. If an export captures the slide before the swap happens, the result may use the wrong typeface or show different line breaks.

Fix: make sure fonts finish loading before export. Preload important fonts and wait until the page is fully loaded. Viewing every slide once before exporting also helps.…