Clicking into a Positron Notebook cell lands cursor in a random location

[howardbaik]

System details:

Positron and OS details:

Version: Positron Version: 2026.06.0 build 211
Code - OSS Version: 1.111.0
Commit: d5f94f0
Date: 2026-05-28T01:04:13+02:00
Commit: 39.6.0
Date: 142.0.7444.265
Electron: 22.22.0
ElectronBuildId: 14.2.231.22-electron.0
Chromium: Darwin arm64 25.3.0
Node.js: undefined
V8: undefined
OS: undefined

Session details:

Python 3.13.7

Describe the issue:

When I press Esc to defocus the cell, and then click on the line beginning with mu, Positron Notebook drops the cursor on a random line instead. See the demo below:

Screen.Recording.2026-06-08.at.11.41.18.AM.mov

[dhruvisompura]

Thank you for reporting this issue @howardbaik!

For triage:
This one is a little tricky to reproduce. I can definitely see this behavior sometimes with a notebook but I can't figure out what the exact repro steps are.

[howardbaik]

FWIW I only see this behavior in large cells (>30 lines of code/comments). I was unable to reproduce this in a small cell (~10 lines).

[rodrigosf672]

This one is a little tricky to reproduce. I can definitely see this behavior sometimes with a notebook but I can't figure out what the exact repro steps are.

Thanks for confirming this happens, @dhruvisompura. I have some consistent repro steps that should work.

1. Have a cell long enough such that it is scrollable (e.g., >30 lines of code/comments, as @howardbaik pointed out).
2. Press Esc and then scroll through the cell.
3. Click on the beginning of your target, desired line.
4. Cursor will land at a different line than the target one.

For the already merged test #14092, it only covers the case of few lines, which currently works. If this issue gets fixed later on, we may then modify that test case to be applicable to this exact, long-running cell (or add a new one).