Z-index is set to 2 --> display issues with dropdowns

[lordlothar99]

As the z-index is set to 2, the dropdown menus are displayed under an input textfield

(see _bootstrap.scss :
.input-group .form-control {
position: relative;
z-index: 2;
float: left;
width: 100%;
margin-bottom: 0;
}
)

[lordlothar99]

Seems to be a duplicate of Field overlaps on other floating elements #17, but no release has been published in Mendix marketplace since then