I have a little problem understanding what an expression like {{ something.render() | safe }} does .
From what I have seen, without the safe ke
Normally text is HTML-escaped (so would be written out as <b>, which would render as ).
When you put |safe after something, you're telling the template engine that you have already escaped the text yourself, i.e. "it's safe to render this directly". So it will not do that encoding for you.
For more information: http://jinja.pocoo.org/docs/templates/#html-escaping