Remove Duplicate Css Rule by Class

Hi @artf , I'm reading and experimenting the setStyle method but when i used setStyle editor.getSelectedToStyle().setStyle({ color: 'red' })

it duplicates the css rule of that class e.g

.class1{
 color: 'black';
}

.class1{
 color: 'red';
}

What I want is either removed the existing class

.class1{
 color: 'black';
}

or update that existing class css rule

.class1{
 color: 'black';
}

This issue is very similar to issue 932. I need avoidInlineStyle: to be set to false since im using inline style.

Please help. Thanks