When new R session failed to start, the Console session picker stops working

System details:

Positron and OS details:

Positron Dev Version: 2026.06.0 build 0
Code - OSS Version: 1.111.0
Commit: Unknown
Date: Unknown
Electron: 39.6.0
Chromium: 142.0.7444.265
Node.js: 22.22.0
V8: 14.2.231.22-electron.0
OS: Darwin arm64 25.5.0

Session details:

I somehow broke my R interpreter trying to get the Connections pane working and I ran into some odd edge cases.

Describe the issue:

When I start a new session and it fails to start, the UI starts to break:

• Notice that the session picker in the top right shows Python, but the Console shows the R session output.
• When I try to click on the Python session in the Console, nothing happens.
• When I delete the failed R session, the Python session finally shows up
• When I copy paste the output of the R session, I get the scrollback history for BOTH the R and the Python sessions.

This is my copy paste. I suspect this is just a leaking hidden DOM elements because the selection isn't constrained to the visible Console, but sharing nonetheless.

Python 3.12.13 (Unknown) started.
Python 3.12.13 (main, May 14 2026, 17:51:53) [Clang 21.0.0 (clang-2100.0.123.102)]
Type 'copyright', 'credits' or 'license' for more information
IPython 8.18.1 -- An enhanced Interactive Python. Type '?' for help.
Automatic import reloading for Python is enabled. It can be disabled with the [python.enableAutoReload setting](vscode-file://vscode-app/Users/brice/posit/positron/out/vs/code/electron-browser/workbench/workbench-dev.html#).
>>>
R 4.6.0 failed to start up (exit code -1)


The process exited abnormally (signal: 6 (SIGABRT))

Steps to reproduce the issue:

Expected or desired behavior:

1. I would expect to be able to switch sessions in the Console.
2. I would not expect the scrollback from another session's console to bleed into what I copy/paste from another session.

Start by reproducing the failed R startup while a Python session is available, then inspect the Console session picker and session output behavior. Confirm that switching sessions works after the failed session and that copied output contains only the selected session's scrollback.