In the Justice League Comic-Con trailer, Barry's lightning streak is blue-ish in color. Does Flash ever have a blue streak in the comics? Or is it something new in the Justice League movie?
Does Flash ever have a blue streak in the comics?
As noted by Alexander Baker on Amino
If you don't remember Flash does have blue lightning in the comics Future Flash
Is it something new in the JL movie?
We actually see Flash with two colors in the movies.
Here he is meeting Batman, with predominately blue lightning.
And here he is racing Superman at the end of the movie. Here it seems like he has a combination of blue and white lightning.
And here we have a future Barry Allen vising Bruce Wayne in Batman v Superman. This older and more experienced Barry is now surrounded by white lightning.