Set the display height of the text element through the height attribute, and display and hide the text element when it exceeds the height through the overflow attribute .
The overflow property specifies what happens when content overflows the element's box. When the element value is set to hidden, the excess part will be hidden.
overflow: scroll;
The overflow:hidden attribute in css makes it impossible to display the drop-down scroll bar in ExtJS.
The overflow attribute:
visible is the default. The content will not be clipped and will be rendered outside the element.
hidden content is trimmed, but the browser does not display scroll bars to view the content.
The scroll content is trimmed, but the browser displays scroll bars to see the rest of the content.
auto If the content is trimmed, the browser displays scroll bars to view the rest of the content.