<TextField
label="Dashboard Title"
onChange={handleChange}
required
fullWidth
value={title}
error={error}
helperText={
<>
This field is required. Only letters and numbers
are allowed.
<br />
Space is not allowed at start. Special
characters are not allowed.
</>
}
/>
참조
https://stackoverflow.com/questions/67264236/textfield-helpertext-spanning-multiple-lines
https://codesandbox.io/s/67264236textfield-helpertext-spanning-multiple-lines-8ul6k?file=/demo.tsx