fails on debian bullseye/sid

No third party libs needed to be built locally

********** SUCCESS ****************
Setup successful.

Attempting to set up UE4 pretty printers for gdb (existing, if any, will be overwritten)…
no ~/.gdbinit file found - creating a new one.

Setting up Unreal Engine 4 project files…

Fixing inconsistent case in filenames.
Setting up Mono
./…/…/…/Source/Programs/UnrealBuildTool/UnrealBuildTool.csproj: error : /home/pepe/gitdwn/UnrealEngine/Engine/Source/Programs/UnrealBuildTool/UnrealBuildTool.csproj: Input string was not in a correct format.
Cannot open assembly ‘./…/…/…/Binaries/DotNET/UnrealBuildTool.exe’: The directory or file does not exist

same behavior under Ubuntu 19.10 :-/

it’s release branch 4.24
should i try older branch?