Practical guide
A File Name Can Reveal What You Meant to Keep Private
Private documents need sensible labels as well as sensible storage. Avoid putting personal details in a file name that others may see.
The label is visible before the document opens
A file does not have to be opened for its name to communicate something. Imagine showing a friend a folder to locate a harmless photograph while another file is named with your full email address and a private community's name. The label alone tells a story. Before saving an account document, consider which details belong in its name. You need enough information to recognize your own file later, but not a miniature account biography displayed wherever you select or attach it.
Choose a useful label without embedding secrets
A restrained name can describe the record type and date without including credentials, recovery answers or message excerpts. For example, Account export September identifies a task more discreetly than a name containing your login address and the subject of a private conversation. Avoid making every file so vague that you cannot distinguish it from the next one. The goal is proportionate labeling, not obscurity for its own sake. Keep any detailed explanation in an appropriately protected record rather than in the public-facing label.
Do not mistake renaming for protection
A neutral name does not change the document's contents or who can open it. Mozilla notes that downloads remain on the computer even after a private browsing session ends. Treat the file's location and access as separate decisions from its label. A private export on a shared desktop remains a private export after you call it Notes. Do not use a discreet filename as an excuse to save sensitive material somewhere unsuitable or to leave the device's normal access controls unattended.
Check the label at the moment of sharing
Before attaching a file or showing a file-selection window, look at the name as the other person will see it. Confirm that you selected the intended document and that its label does not expose information irrelevant to the task. Renaming an attachment for clarity should not misrepresent what it contains. You can explain that it is a limited account record without reproducing the private subject in its name. The takeaway is simple: review a document's outside label alongside the material you intend to disclose inside.
Sources checked
Linked reference pages checked on 2026-09-09. Product details can change. No paid-membership test or sponsorship is implied.
Mozilla: private browsing and downloaded files ↗