RTE Output escaping html sepcial character (e.g. & < >)

Ages ago (last year), I have an issue with RTE inside Sitecore, whereby it tries to escape html special character. E.g. for this is

Solution:

It is proper behavior. Imagine that you will output this RTE text on the frontend. Then ">" and "&" could be read as parts of tags or reserved symbols, so such characters are always escaped.
But you can try to add your handler to save HTML in different way. This could be done by the next steps:

If you make such changes, be sure that you handle double meaning situations properly.