...
There are two fields dedicated to filling out a description.
The first field enables you to write a short description that will appear in search engines. This field is limited to 400 characters. The text editors editor's options here are useless, as HTML only uses plain text.
In the second field, you can write a full description of your product, which will appear directly on your online store. The text editor offers a wide range of options for creating visually attractive descriptions (font, size, text color, etc.).
While the second form has no limits, there is such thing as too much content: put the essential information in an a compelling way, and your product should be good to go.
...