Bright dot changes in fullscreen? How to check

A bright dot stays on your screen, but looks different or disappears when you enter fullscreen. That change can point to a browser overlay, a graphics or display-mode issue, or a pixel that responds differently to certain colors. Fullscreen behavior alone does not prove the screen is broken.

Compare the dot in the same place under a few solid colors, then check whether it appears outside the browser. The Display Test can help you inspect color screens, and the Stuck Pixel Fixer offers a flashing pattern to try only after you have identified a likely stuck pixel.

Check the bright dot in and out of fullscreen

1. Open the Display Test and look at the dot on several solid colors. Note whether it is bright on every color or only on some backgrounds.
2. Keep the same color visible and enter fullscreen using the browser or test's fullscreen control. Look at the same physical spot on the screen, then leave fullscreen and compare.
3. Change the page or color while staying fullscreen. If the dot moves with page content, it is likely part of a page, overlay, or graphics rendering rather than one physical pixel.
4. Check the same spot in another browser or app, and on the desktop. If possible, connect the display to another device or use a different monitor input.
5. Take a screenshot when the dot is visible, then view that image on another screen. A dot in the screenshot suggests it is being drawn by software. A dot missing from the screenshot may be in the display or somewhere in the output path, but this test is not conclusive by itself.

Do not press or rub the spot. That can damage the panel and will not reliably repair a pixel.

What the result means

The dot follows an object or appears in the screenshot

The mark is probably in the page, a browser extension, a cursor highlight, or another software overlay. Close floating menus and overlays, then try a private window or another browser. If the mark appears only in one app, check that app rather than treating it as a panel defect.

The dot stays in exactly the same screen position

A spot fixed to one physical location across different pages and colors may be a pixel or subpixel problem. A subpixel is one of the tiny red, green, or blue parts that make up a pixel. Some stuck subpixels appear bright on particular backgrounds and less obvious on others. See Fixed dot on screen: overlay or stuck pixel? for more ways to tell the difference.

The dot changes only when fullscreen starts

Fullscreen may change how the browser presents the image, but it does not always change your screen's resolution or refresh rate. If the dot appears, shifts, or changes brightness only during fullscreen, suspect a browser rendering issue, graphics setting, or display mode before concluding that the panel has a bad pixel.

The dot appears on another input or device too

If it stays at the same physical location when you change input sources or connect another computer, the display panel is more likely to be responsible. If it disappears with another source, check the original computer, cable, adapter, or graphics settings.

How to narrow down the cause

1. Reload the page and close overlays. Close browser menus, picture-in-picture windows, screen filters, and extensions that draw over content. Reopen the test and compare again.
2. Compare another browser and app. Check the same solid color in a different browser, then in a desktop app. If only one browser shows the dot, update or restart that browser and temporarily disable extensions.
3. Check display settings. On Windows 11, open Settings › System › Display. Compare the result with HDR off if that option is available, and check Advanced display for the selected refresh rate. On macOS, open System Settings › Displays and compare available display or refresh-rate options. Change one setting at a time, then restore it if there is no difference.
4. Reconnect the display path. If you use an external monitor, unplug and reconnect the cable at both ends. Try another port or cable, and connect directly to the computer instead of through a dock or adapter.
5. Restart the browser and computer. A restart can clear a temporary graphics or browser state. Repeat the same color and fullscreen comparison afterward.
6. Try the flashing pattern only if a stuck pixel seems likely. Open the Stuck Pixel Fixer and use its pattern briefly. Stop if the flashing causes discomfort, a headache, or eye strain. Flashing patterns may be unsafe for people with photosensitivity, so skip this step if that applies to you.

For a safer way to inspect a screen mark without rubbing it, see How to inspect a screen defect without rubbing it.

When it's likely to be the hardware

A bright spot is more likely to be a panel defect if it stays in one physical position across different colors, apps, browsers, inputs, and connected devices. A dot that remains bright on black or changes color independently of the image can be a stuck subpixel. A software test cannot confirm the exact panel fault or guarantee a repair.

If the display is new or still under warranty, photograph the spot on a plain background and ask the seller or manufacturer about its pixel policy before attempting any fix. If the spot is growing, accompanied by lines or flickering, or visible across multiple inputs, contact the manufacturer or a repair shop. Avoid applying pressure to the panel.

Why fullscreen can change what you see

Fullscreen can hide browser controls and change the area used to draw the page. Depending on the device and settings, it can also coincide with a change in HDR, refresh rate, scaling, or graphics behavior. Those changes can make a pixel defect easier or harder to notice, even when the defect itself has not changed.

Use the same solid color and viewing angle for each comparison, and give your eyes a moment to adjust after changing modes. If the dot appears only during rapid flashing, stop the pattern and check the screen with steady colors instead.