Environment Data

• VS Code version: 1.99.3.0(not relevant)
• Jupyter Extension version: 2025.3.0 (however, even 2020.2.0 applies, so it doesn't matter)
• Python Extension version: 2025.4.0(not relevant)
• OS: Windows 11 24H2
• Python and/or Anaconda version: 3.8, 3.11 and 3.12(not relevant)
• Type of virtual environment used: conda(not relevant)
• Jupyter server running: Local and Remote(not relevant)

Expected Behavior

Exporting a Jupyter notebook to PDF from the VS Code Jupyter extension bar, and get a pdf.

Actual Behavior

Failed to export.

Steps to Reproduce

1. Open any .ipynb file in VS Code.
2. Right-click and select "Export as PDF".
3. Observe the export failure, despite a valid PDF existing in the temp directory (for example "C:\Users...\AppData\Local\Temp\tmp-53764aZammKviOmV0.pdf.pdf").

Additional Information

1. available options

2. This issue is distinct from Can't export a pdf. The html export works fine. #13912, xelatex (TeX) installed but still giving error #10910, and Export to pdf failed #12742, which suggest pandoc or nbconvert problems. These are not the root cause.
3. root cause: pdf is actually generated, however, the extension failed to get his name. For example, the true ath is ...\AppData\Local\Temp\tmp-54084AG2zf2BvEQSm.pdf.pdf, but the extension accesses ...\AppData\Local\Temp\tmp-54084AG2zf2BvEQSm.pdf and thus got a failure.
4. The code snippet from src/notebooks/export/exportBase.node.ts, if((await this.fs.stat(Uri.file(tempTarget.filePath))).size > 1) await this.fs.copy(Uri.file(tempTarget.filePath), target); is the source of the error. tempTarget.filePath contains the correct temporary filename (e.g., ...\AppData\Local\Temp\tmp-54084AG2zf2BvEQSm.pdf), but the extension is looking for a file with an extra .pdf extension.
5. A temporary workaround is to modify the code to if((await this.fs.stat(Uri.file(pdfFilePath + '.pdf'))).size > 1) await this.fs.copy(Uri.file(pdfFilePath + '.pdf'), target);.