Rocket Validator integrates the W3C Validator HTML checker into an automated web crawler.
HTML issues tagged as multiple.
The multiple attribute is used to indicate that multiple options can be selected in a <select> element. As a boolean attribute, it should only be declared without any value.
You should use:
Here is an example of the correct usage of the multiple attribute:
<label for="colors">Select your favorite colors:</label> <select id="colors" name="colors" multiple> <option value="red">Red</option> <option value="green">Green</option> <option value="blue">Blue</option> <option value="yellow">Yellow</option> </select>
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