Tor bridge warning: could not format extend cell?

I want to run a tor bridge in a docker. The system is Debian 10.6. I downloaded Tor source code from I tried and They will all show the following warnings after launch. I just wonder whether it matters or not. I did not get such warning with

No real answer to your question, but are you aware that such a Docker image already exists?

Thank you for your help! But I want to use my own docker. BTW, I have seen the same log on my Mac Tor before. Would be great if someone knows what this means.