I can not remove the dashed border that comes up when I click on an item in a combo box, I already tried the outline: none feature of css3, but it did not work. Can anyone help me?
Ex:
The drop-down with options is part of what's called ShadowDOM . In current CSS level 3 specifications, there is no way to achieve most ShadowDOM elements. You can read the specs about ShadowDOM here , though there is not much there about what you want.
But there are options like Select2 that redraws the entire combobox using Javascript.
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