She sent a communication which read

The Speaker's rooms, Washington, D.C., January 11, 2021. I hereby appoint the honorable Debbie Dingell to act as Speaker Pro Tempore on this day. Signed, Nancy Pelosi, Speaker of the House of the United States.

EDIT: heres a stream of the hearing: (https://www.youtube.com/watch?v=U4t60lQn_DE) Skip to 12:25

EDIT 2: the video appears to have been edited the relevant part is now from 0:03 to 0:30