Xrm.Page.data.entity.save() change focus on CRM Form in crm2015 onpremis

I have a javascript code that the function  Xrm.Page.data.entity.save() called on it . 

when this function is called the focus changes on the form and a tab expanded on it automatically. 

I tried calling the Xrm.Page.ui.tabs.get("a").setDisplayState(COLLAPSED) before saving it;

but nothing changed . Does anybody know why this happened?

i had another problem with save on crm form that cleared the value of a disabled field on from . 

after enabling the field the bug solved. But still i want to disable the filed before saving it .