The aria-labelledby attribute gives labels to elements that don't usually have them.
Here is an example of how it could be used:
Although the above sample works, this is a bad example of its use as a label should be used for input elements.
The first rule of aria attribute usage is don't use aria! There is usually a better way of solving your accessibility problem with standard HTML.
aria-labelledby should only really be used if you are assigning labels to elements that don't usually have labels, these would include: div, span or areas. You'd likely want to use it if these elements were used as alternatives to form elements? But why are you using form element alternatives?
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