Reported: clicking "Open Downloads folder" was opening the Documents
folder instead of Downloads. Root cause is the classic Windows
gotcha: when the path contains a space (e.g.
``C:\Users\Michael Dombaugh\Downloads``), Python's
``subprocess.Popen`` packs the ``/select,...`` argument into a single
quoted token, and Explorer's ``/select`` argument parser does NOT
accept that form — it silently falls back to whatever the user's
default Explorer view is (typically Documents).
Resolution paths considered:
- ``shell=True`` with a hand-built command string — works but opens
the door to shell-injection if a file_name ever contained a quote
or special char.
- ``cmd /c start "" explorer /select,...`` — same parsing issue.
- ctypes ShellExecuteW — pulls in a Windows-only dependency.
- **Skip /select. Open the folder directly.** ✓
Going with the last. ``explorer <folder>`` reliably opens the folder
regardless of spaces in the path; the user finds the freshly-saved
file by its name. The previous "highlight the file" nicety wasn't
worth the path-parsing fragility — every user folder on Windows is
``C:\Users\<name>`` and every Windows username can contain a space.
macOS keeps the ``open -R <file>`` reveal-in-Finder path because
macOS argument parsing is sane and that's a strict UX win.
2220 tests pass.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Michael
42f8d78dd5