From this paper
The first phase of stellar evolution in the history of the universe may be Dark Stars (DS), powered by dark matter (DM) heating rather than by nuclear fusion.
Although made almost entirely of hydrogen and helium from the Big Bang, they form at the centers of protogalaxies where there is a sufficient abundance of DM to serve as their heat source. They are very bright diffuse puffy objects and grow to be very massive.
In fact, they can grow up to ten million solar masses with up to ten billion solar luminosities.
In this paper, we show that the James Webb Space Telescope may have already discovered these objects.