*Steps to reproduce:*
# Create a new URP project.
# Import the extracted contents of the attached Editor.zip.
# Open Assets > Editor > SimpleCustomEditor.uxml in UI Builder.
# In the UI Builder, add a new selector to mysheet.uss and add that selector to #button1. Save your changes.
# Window > UI Toolkit > SimpleCustomEditor.
# Click the vertical ... menu icon > UI Toolkit Debugger.
# Click Pick Element in the Debugger, then click on the red button in SimpleCustomEditor.
# Expand Matching Selectors section.

*Actual results:* Your new selector's button says mysheet.uss:-1

*Expected results:* It should be mysheet.uss:12 , or whatever line that new selector is on when you open mysheet.uss in a code editor.

*Reproducible with versions:* 6000.1.0a4, 6000.0.28f1, 2022.3.52f1, 2022.2.0a17

*Can't test with versions:* 2021.3, not supported on OS

*Tested on (OS):* Ubuntu 24.04

*Notes:*
* Issue is resolved after an editor restart.