Usage
Input groups can combine multiple elements. For example you could add buttons to 1 or both sides of a text input, like in a search field or an email input field.
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When to use
Use an input group when the elements are directly connected to each other. Examples include an action button to act on the text, a mandatory and fixed piece of text, a class of text when in a filter, a unit of currency, and more.
When not to use
Do not use an input group when you're performing different actions on the item, such as a text entry and a remove action.
View more examples in the input group react tab.
View source on GitHub