The Brooklyn Book Festival will be back for its fifteenth year from September 28 to October 5, but not in its usual location in front of Borough Hall (photo). This year, thanks to COVID-19, it will be held on line. As Kevin Duggan reports in The Brooklyn Paper, one of the Festival’s co-producers sees a bright side to this:“This really expanded the opportunity to bring in audiences from different time zones, as well as authors for whom in the past might have been very difficult to travel to the festival,” said Liz Koch, one of the fest’s co-producers. “Literally this year everyone can have a front row seat to this festival because they’re right at their laptop.”Nevertheless, your correspondent will miss the opportunity…