Broken UI-dailogs with z-index problem

Hello all,

I am using Frappe 6.27 version

following classes have problem with z-index values.

ui-autocomplete 
ui-front 
ui-menu 
ui-widget 
ui-widget-content

In default jquery-ui.selected.css

.ui-front{
z-index: 100;
}
Here for ui-front : 100 ; menu elements goes below other elements which make them disappear below some other UI content.

So I made ui-front : 100 important!;
then all the link fields on scrolling are kept top on header which looks very odd.

In default desk.css

.modal .link-field .ui-autocomplete {
  z-index: 1141;
}

I have seen update from @netchampfaris on yet another z-index fix by netchampfaris · Pull Request #2248 · frappe/frappe · GitHub

But still there are same problems. Even In some cases for chrome version below V50,all this works okay and from v50 we see UI errors.

How can I properly set this to avoid the UI problem.

Thanks in Advance.

Can you share screenshots please.

@rmehta Sir this are those screenshots

For Z-index = 100 important!:

For Z-index = 100 :

Care to push a fix?

CC @netchampfaris