Our source view is based on Monaco, a version of the Visual Studio Code editor that runs in the browser and provides many of the same features (search, thumbnail view, syntax highlighting, etc).
As noted previously, the Pernosco service does not need access to application source code. The Pernosco web client can load source code from private servers that our Pernoco service can't access.
The source view provides annotatations of the lines that were executed in the current function activation. We are working on adding more annotations, such as changes in the values of variables.
The user can click on a line in the source view to show executions of that line before and after the current moment.