# Mathematical Formula in NEOS7 CMS

Hi Team,
I am new with Neos, I am trying to implement mathematical formula in neos cms editor. https://ckeditor.com/cke4/addon/mathjax
I am not sure the neos7 default ckeditor version.

Hello and welcome to the Neos Community,

the default editor is ckeditor 5. But we have not the math plugin installed. So you probably need an extension of the ui for that.

We have some examples for that.
But not sure if there is also a ckeditor plugin for cke5 available.
neos/neos-ui-extensibility-examples: Neos UI Extensibility Examples (github.com)

@markusguenther Thank you for your valuable reply, I will go through the example.
It would be helpful if there is tutorial or document available for extension/package development so we can understand the code flow.
Actually we have the third party package for mathematical formula in ckeditor (with mathjax) but it works till neos 4.3, after upgrade it to Neos 5.3 or Neos 7 it stops working.
I am not sure which syntaxes are deprecated and required to change according to neos 7 from this package.

The ckeditor is configureable. So maybe just change the inline editor to version 4. The default is version five.

Neos.Neos.UI.frontendConfiguration.defaultInlineEditor: 'ckeditor5'

Did not that for such a long time but I bet you just set it to ckeditor instead of ckeditor5.
Just a guess. Maybe give it a try

@markusguenther Thanks a lot, it works with ckeditor4.

after upgrade to neos 7 “Neos.NodeTypes.ColumnLayouts:TwoColumn” also not rendering old content. we can create new two column layout but old created twoColumn layout content is not rendering.
Any solution on it?