Support for Drupal 7 is ending on 5 January 2025—it’s time to migrate to Drupal 10! Learn about the many benefits of Drupal 10 and find migration tools in our resource center.
The number of rows for textarea for the description of the taxonomy term by default is 5, but in category module taxonomy term is a node and it is not enough for work with node text.
At editing with the WySWIG editor there is no possibility to change allowed textarea height, and 5 rows it is not enough height.
In category.module should be
$form['body_field']['body']['#rows'] = 20; //increase textarea height from 5