Outline view disappears after adding new section headers in R scripts

Describe the bug:
The outline view in VS Code initially displays symbols (functions, sections) correctly when an R file is opened. However, once I add a new section header (e.g., # Testing ----), the outline view disappears and shows "No symbols found in document". This makes it difficult to navigate larger R scripts as the document structure is lost whenever I edit the file.
To Reproduce:

Open an R script that contains some functions and section headers (# Section name ----)
Observe that the outline view correctly shows these symbols
Add a new section header (e.g., type # Testing ----)
Observe that the outline view now shows "No symbols found in document"
The only way to temporarily restore the outline is to close and reopen the file

Can you fix this issue by yourself?
No

settings.json:

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}

Expected behavior:
The outline view should remain functional and continue to display all symbols even after editing the file or adding new section headers.

Environment:

OS: macOS
VSCode Version: 1.98.2
R Version: 4.4.3
vscode-R version: 2.8.4

Additional context:
I've tried reinstalling the R extension and configuring the language server settings, but the issue persists. The outline view works correctly with other file types (e.g., Python) but consistently breaks when editing R files. The R Language Server does appear to be running correctly according to the logs.

Reproduce the issue in VS Code with an R script containing functions and section headers, then add a new header such as # Testing ---- and inspect the R Language Server logs. Verify the outline behavior before and after editing. Done means the outline continues to show all symbols after new section headers are added.