ExtJs problem or laziness?

Question

JavaScript

Good morning.
Testers accept a project from one developer and push a bug along a tree built on ExtJs:
“A folder that does not have folder descendants, but has an element binding (which are not shown in the tree) still has an expansion marker (arrow), although it should not.”
The developer replies "This is how ExtJs works." Is it so?

Answer 1

Depends on the salary and level of the developer.

Answer 2

Extjs? No, have not heard