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+# Developer Notes
+
+This document is for the `dev` branch only. Do not publish it on `main`.
+
+## Screenshot and Testing Startup Switches
+
+Taskbar Launcher supports a few command-line switches to open specific UI surfaces for documentation screenshots and manual testing:
+
+```powershell
+TaskbarLauncher.exe --show-settings
+TaskbarLauncher.exe --show-about
+TaskbarLauncher.exe --show-launcher
+```
+
+- `--show-settings` opens the Settings window after startup.
+- `--show-about` opens the About window after startup.
+- `--show-launcher` opens the launcher popup after startup.
+
+These switches are not part of the normal user workflow. They exist so development and documentation captures can be repeated cleanly.