I followed the instructions of @brunekninja, but have the same problem as @thewhipster: Fatal error: Class ‘Roots\Soil\Nav\NavWalker’ not found.
I’m using Trellis/Bedrock/Sage 9 beta 4, with Soil installed and activated.
The same question was asked here, but never resolved.
Any other thoughts on why the class can’t be found, even though Soil is installed and activated?