When I first checked this poll, Biden was ahead with about 56 %. I checked it again about an hour after the debate ended and found this.
BTW, abc7 dot com is the website for KABC-TV in Los Angeles. That suggests these poll numbers are mostly driven by California voters.
UPDATE— As I was about to hit the PUBLISH button, I checked the poll again. Trump was up to 56 %, and the percentage of vote switchers was up to 6 %.