When I run the "bundle exec middleman build" command, I get an warning and the process hangs, and I can't generate html

[alexmao1024]

When I run the command "bundle exec middleman build", I get the following information

== Sprockets will render css with ruby sass
consider using Sprockets 4.x to render with SassC
create build/stylesheets/print-953e3353.css
create build/stylesheets/screen-90a7251f.css
WARNING: V8 isolate was forked, it can not be disposed and memory will not be reclaimed till the Ruby process exits. It is VERY likely your process will hang. If you wish to use v8 in forked environment please ensure the platform is initialized with: MiniRacer::Platform.set_flags! :single_threaded

Then the command hangs and can't continue to run.

I am new to Ruby and I am only using this project to write documentation, I am not sure how to follow the warnings to change them or if the problem is with the warnings, can someone help me?

I ran the command on Windows WSL Ubuntu 18.04, and the command "bundle exec middleman server" worked