Fleet .NET project. Missing dependencies

Question

I've added a new reference to a .net console project but in the Solution tab in Dependencies/Projects, a newly added reference is missing there. My program .csproj looks like this:

<Project Sdk="Microsoft.NET.Sdk">

  <ItemGroup>
    <ProjectReference Include="..\DigitalFilterAnalyzer\DigitalFilterAnalyzer.csproj" />
  </ItemGroup>

  <PropertyGroup>
    <OutputType>Exe</OutputType>
    <TargetFramework>net7.0</TargetFramework>
    <ImplicitUsings>enable</ImplicitUsings>
    <Nullable>enable</Nullable>
  </PropertyGroup>

</Project>

The first time I tried import my namespace it showed me a message: "Cannot resolve symbol ...". I did not have any code suggestions for my namespace while typing its name. So I tried to build the current solution and it worked.

But the reference project did not appear in the Dependencies in the Solution tab.