I tried to build a small example and this is the result i got.
first i generate a new project with cmd
then i changed the "sencha.cfg" to get neptune theme
>sencha -sdk "D:\sencha cmd\Sencha\ext-184.108.40.2063" generate app Myapp "D:\sencha cmd\myapp"
then i ran
then this is the result i get
>sencha app refresh
>sencha app build
when i run index.html from "build/Myapp/production" result is tabpanel's left border is missing.
is it something im doing wrong or something wrong with sencha cmd?