Issue with dynamic strings

[simofacc]

Hi,

I am trying to use dynamic strings e.g. flag-${country.id} but the prefix is not being added.

e.g.
const flag =flag-${data.leagueId}; <span className={classNames('flag', flag)}></span>
The first class 'flag' is prefixed but not the dynamic one.

[seunggs]

Same problem here

[eguyot]

Same here. When I use a concatenation, it doesn't work.

className={btn btn-facebook ${this.props.className}}

Is there any way to make this work ?