bootstrap formidable with error messages

i found this post:

https://formidableforms.com/help-desk/bootstrap-disabled-field-error-message/

The Problem: by default, the error messages won't appear anymore. Steph's code will show them again but it looks not nice.

to achieve both styling and usablity i came up with some less code. this requires the usage of bootstrap.less ! you have to compile your own .css file with a less compiler! if you do so, you can use the following code:

.frm_required_field.frm_blank_field {
    .has-feedback();
    .has-error();
    .frm_error {
        display: block;
        position: absolute;
        left: @grid-gutter-width/2;
        top: 100%;
        color: @brand-primary;
        font-size: 12px;
    }
}