Expected behavior

Labels are visible after opening the select contents.

Actual behavior

If a parent (it doesn't matter at which level) of the .mdb-select element has a background, the label isn't visible. This is caused the property z-index of the label itself which is set to -1. Changing the z-index to a higher value (e.g. 1) fixes this issue, but causes subsequent problems. In this case the select-wrapper won't show the dropdown-contents if you click on the label directly (but aside it), since it's not recognized by the event listener.

Resources (screenshots, code snippets etc.)

See https://mdbootstrap.com/docs/jquery/forms/select/#color In the Example, simply add the style background:white to the div.section-preview, which will immediately hide all labels in the example. Changing the z-index to one for label.mdb-main-label elements will show the labels, but causes the described issue of clicking the label.