monorepo CI/CD pipeline using one a single pipeline for my forntend and backend in codepipeline

A pipeline can have multiple CodeConnections sources (GitHub), and each source can have it's own triggers (or not have triggers). So you can define a pipeline that has two sources pointing to the same repository, but with different filters for file paths - one for frontend and one for backend. When a change in either the frontend or backend file path is received, a new pipeline execution is started with the source that triggered the pipeline cloning the specific commit, and the other source cloning the HEAD commit. You can also have a pipeline with a trigger for frontend source and no trigger on the backend source.

Can you explain what the single pipeline that will be triggered for changes from both frontend and backend paths will do?