How to switch between Rich Text/Rich Text (old)/Markdown editor?

HelpLook supports switching Rich text/Rich text (old)/Markdown editor, there are two methods：

① As shown in the figure, in the document editing page, click the upper left corner of the page can choose to switch the editor.

*Rich text is the latest editor, there are Merge cells, Find and replace, Emojis and other advanced functions. Newly created sites and documents will no longer display the Rich Text (old).

*Switching editors requires an empty document and a published state

②Switch the Rich Text Editor/Markdown Editor on the Site Settings page. Site Settings->Site Information->The Default Editor