I have a question about my Physics Stack Exchange post: A new way to define matrix-vector products, to relate physical fundamental constants and units of measure
I'm trying to convert my post to MathJax, but since it's a long post, I cannot "see what I get", while writing those complex MathJax expressions "blindly" does not help...
Having the editor side by side with the preview would be better to me, while just adding a scrollbar to the preview too (only the editor has one) would still work and would require very small changes in the Stack Exchange UI.