Preview files and choose an opening app

Inspect a file without changing its opener

1. Select one local, available file and press Space for Quick Look.
2. Check that the preview corresponds to the selected file. Some formats depend on macOS preview support; an unsupported preview does not necessarily mean the file is damaged.
3. Close the preview and open the file with double-click or Command-Down when you are ready. Return renames the item instead.
4. If a cloud file is online-only, decide whether to download it first. Previewing contents can require bytes that ordinary directory browsing does not.

Choose an application deliberately

1. Select the file and open its context menu. Use Open With for a one-time app choice.
2. If using Always Open With, read the scope of the rule in the chooser before saving. A persistent rule should be intentional, not an accidental consequence of one opening.
3. Test the rule on a disposable file of the intended type. A rule for one extension must not be assumed to cover every file or a file with no extension.
4. If a file opens in the wrong app, review the saved opening rule and the Mac's own association. Changing a filename extension just to force an opener can create confusion.

Understand saved opening scopes

• This file: a specific file rule in Pathem.
• Files in this folder: a folder-scoped rule in Pathem.
• All .extension files (system-wide): changes the macOS default for that file type, affecting Finder and other apps too. For a name without an extension, the exact-name option is limited to Pathem instead.
• Just this session: a temporary selection that is not the same as changing the system default.

Copy a file versus copying its name

Copy writes a file reference for receiving applications that accept file attachments. Copy Path, Copy Name, and Copy as File URL are different commands with different results. Use Copy Name when you specifically want text, not an attachment.

When pasting into a message, inspect the unsent attachment and filename before sending. The receiving app can import, rename, convert, or choose a different clipboard representation; drag-and-drop and keyboard paste are not guaranteed to use identical import paths in every application.

If a recipient app changes a filename, compare the same harmless file using Copy/Paste and a drag into an unsent draft. Record the app, source action, and result without sending private test data. Do not assume a successful file copy means the receiving app preserved every piece of metadata.