linux – Nginx error logs: what does “pagespeed: rollback gzip, explicit configuration in /etc/nginx/nginx.conf:151” mean, and how can I fix it to use brotli?

I am running an Ubuntu 20.04 LEMP server with the pagespeed and brotli module for Nginx. In my /var/log/nginx/error.log I am seeing the following error:

2023/02/23 07:34:49 [info] 1553667#1553667: [ngx_pagespeed 1.15.0.0-8811] No threading detected. Own threads: 1 Rewrite, 1 Expensive Rewrite.
2023/02/23 07:34:49 [info] 1553667#1553667: pagespeed: rollback gzip, explicit configuration in /etc/nginx/nginx.conf:151

What exactly does this mean? Does this mean nginx pagespeed is abandoning Brotli compression and rolling back to gzip? How can I fix things so that this error no longer appears, and ensure that the brotli module stays active using brotli compression even while the pagespeed module is active?