Full screen hides the menu bar. That is not protection.

Full screen does hide the menu bar. It is also the most common reason people think they have already solved this, and it is worth being precise about what it does and does not do.

What full screen changes

Full screen is a property of a window, not of the display. When you put an app into full screen, macOS gives that window its own space and hides the menu bar inside it. Move the pointer to the top edge and the menu bar slides back down. Move away and it retracts.

While you stay inside that window, the top strip of the panel shows your app instead of the menu bar. That is real. Those pixels are being driven with varying content, which is exactly what you want.

The protection is tied to the window. It is not a setting that persists across your session.

Where the exposure goes instead

Think about the shape of an actual working day rather than a single long session.

You leave the full-screen window to check a message. You switch to the Finder to drag a file in. You open Mission Control to find the other window. You quit the app when you finish and sit on the desktop for a minute. You wake the Mac in the morning and the desktop is what greets you.

Every one of those moments puts the menu bar back on screen, at full brightness, in the same row of pixels it always occupies. The bar does not move. The clock sits in the same place. The battery icon sits in the same place.

Burn-in is cumulative. It does not care that the exposure arrived in short pieces. Ten minutes of desktop, six times a day, is an hour a day on those pixels, and it is an hour on the highest-contrast content the panel will show all day: white glyphs on a fixed background.

The second-display problem

If you run a laptop next to an external monitor, the menu bar is on whichever display is frontmost. On a multi-display setup with the menu bar mirrored to both, one of them is showing it while you work full screen on the other.

Full screen on the display you are looking at does nothing for the display you are not looking at. That is the case where people are most surprised, because the protected feeling comes from the screen holding their attention.

We have a separate piece on hiding the menu bar on an external OLED only, because the fix there is different.

Auto-hide gets closer, and still leaves the gap

macOS has an auto-hide setting for the menu bar, in System Settings under Control Center. It is a genuine improvement over full screen because it applies to the desktop as well, not only inside a window.

It still reveals on hover, and the reveal is the whole bar at full brightness. If your pointer travels through the top of the screen often, and most people's does, you are triggering the exposure you were trying to remove. We compared the two in auto-hide versus TuckBar.

What reduces the exposure

Ranked by how much they help:

1. Display sleep. A sleeping display draws no current for those pixels, so the wear stops rather than moves. This is the strongest thing macOS gives you and it costs nothing. See screen sleep and screen savers.
2. Hiding the bar outright, so it is absent rather than one hover away.
3. Auto-hide, which helps on the desktop but keeps the hover reveal.
4. Full screen, which helps only while you are inside the window.

Full screen is on that list. It is at the bottom, and it is the one people rely on hardest.

The short version

Full screen protects the pixels while a full-screen window is frontmost. A working day is full of moments when one is not, and those moments are spread across every hour you use the machine.

If you already work full screen most of the day, you have removed a good share of the exposure. The remainder is not small, and it lands on the same fixed row of pixels every time, which is the specific pattern that causes the problem.