# Side by side editor that supports LaTex or Mathjax or similar **and** Markdown?

Writing and editing long entries in stackexchange can be cumbersome. I recently found stackedit.io which is great way to write and edit the longer entries. It has:

• side by side editor/preview
• Markdown support (via Pagedown)
• Katex support (e.g.  and ) However, it's lacking one thing: support for LaTex things such as: \begin{align} ... \end{align}  • As I had occasion to point out previously, StackEdit supports \begin{aligned}...\end{aligned}. It has been close enough for my wysiwyg needs. Dec 15, 2021 at 7:31 • Thanks! I just tried it out and it didn't work -- at least I didn't see it in the preview -- maybe it works when existing to pdf? But I'm trying to get it to work for preview. Dec 15, 2021 at 14:41 • No it doesn't have anything to do with PDF export. Thanks for trying. I just checked one of my existing files there and it works for me (in the displaystyle ....$$ environment). Dec 15, 2021 at 14:58 • Gotcha. It worked like that and so did $$\begin{align} ... \end{align}\$. Dec 15, 2021 at 15:54