debug doesn't open source file when used on renv installed packages

System details:

Positron and OS details:

Positron Version: 2025.09.0 build 139
Code - OSS Version: 1.103.0
Commit: 30e3d0a74e09a0f6640929822cb57a326671360e
Date: 2025-08-29T18:34:16.368Z
Electron: 37.2.3
Chromium: 138.0.7204.100
Node.js: 22.17.0
V8: 13.8.500258-electron.0
OS: Linux x64 6.12.10-76061203-generic

Session details:

R 4.4.1

Describe the issue:

When debuging a function, I get a file opened, with the debugger enabled, on functions installed in the base system library. When I try the same thing on a function from a library managed by renv, the file "can't be opened".

I've tried updating to the latest version of renv, and re-installing the dplyr package (rebuild = TRUE) in the example below, and I still get the error.

Steps to reproduce the issue:

1. Use renv to manage packages.
2. Install dplyr.
3. Try to debug a mutate call.

Expected or desired behavior:

The file is opened, and debugger runs properly.

I am attaching two screencasts, one where I am performing the debug using a non-renv managed session, and one where I am.

Works:

https://github.com/user-attachments/assets/39774416-536b-49c7-89e3-8edbdfee08b0

Fails:

https://github.com/user-attachments/assets/d67111df-4ec2-4aa3-a150-5bcc0274557a

Were there any error messages in the UI, Output panel, or Developer Tools console?

Start by reproducing the issue with an renv-managed dplyr installation and compare it with debugging the same mutate call outside renv. Trace the source-file opening path for the debug session and use the reported UI error as the failure signal; done means the package source file opens and the debugger runs properly.