TinyMCE escapes quotes

I’m having some problems with TinyMCE editor. When I add attributes to headers ( h1, h2, h3 .. ) it escapes the attribute.
Example: <h1 title=”\”test\””>test</title> this is what it returns instead of <h1 title=”test”>test</title>

But it does work good for paragraphs. What should I do? Please help!

Problem is on this page: https://cippodesign.com/cippo-design-services on title “Web design & branding”