It seems that one of the last updates broke Pinta. When starting from shell, the following error occurs:
You must install or update .NET to run this application.
App: /usr/lib/pinta/Pinta.dll
Architecture: x64
Framework: ‘Microsoft.NETCore.App’, version ‘6.0.0’ (x64)
.NET location: /usr/share/dotnet/
The following frameworks were found:
7.0.0 at [/usr/share/dotnet/shared/Microsoft.NETCore.App]