select2-height bootstrap 4 code example

Example: .select2-selection__arrow { height: 34px !important; }

.select2-selection__rendered {
    line-height: 31px !important;
}
.select2-container .select2-selection--single {
    height: 35px !important;
}
.select2-selection__arrow {
    height: 34px !important;
}