Preview function (especially for LaTeX)
It's often the case that you want to type some LaTeX formulas (thanks for that support) and then you're wondering that there is no formula shown due to a mistake (e.g. begin instead of \begin)
This could be improved by introducing a preview-function. The LaTeX formula could be created, when the closing $$ have been typed or maybe when the user presses a button or a key combination or something else.