City Hall is on track to kill one of the few silver linings of the pandemic: outdoor dining. It banned the use of most outdoor heaters in May; if it doesn’t allow them, most restaurateurs have no practical alternative.

Hundreds of struggling restaurants relied on propane-fueled heaters to attract outdoor customers until May, when Team de Blasio suddenly nixed them with no notice or advanced warning. It was a moot issue for months — but with cold season looming even as many don’t feel safe dining inside, it’s now a dire question.

Other alternatives are either too impractical (electric heaters) or expensive (hooking up to a permanent natural-gas line). And no other major city prohibits propane-fueled heaters. This is just a foolish precaution when no safety issues have emerged, and propane even entails 43 percent less greenhouse-gas emissions than electricity.

Jason Birchard of East Village eatery Veselka, with limited indoor seating, says a propane ban will slam his business again as the weather cools: “With all that we’ve had to deal with” since COVID hit, “it seems like the city wants to make life more difficult for me.”

Don’t hit restaurants and diners again: Reverse the ban.