Dead, stuck, and bright pixels are different observations
An LCD pixel is commonly made from red, green, and blue subpixels. A point that stays dark on white and the three primary colors is consistent with one or more subpixels staying off. A red, green, or blue point visible on black is consistent with a lit or stuck subpixel; a white point on black can involve all three. These labels describe what the panel shows, not a browser diagnosis of the failed transistor.
Classify the point with black, white, red, green, and blue
Clean the screen without pressing it, enter fullscreen, and inspect the same physical location on every field. Note whether the point is dark, bright, or colored on each background. Move the browser window and change the displayed content: a panel defect stays fixed on the glass, a content or GPU artifact moves with the image, a reflection changes with viewing angle, and surface dirt may wipe away. A screenshot viewed on another display helps separate rendered-image faults from panel faults.
Document safely before warranty or repair decisions
Photograph the point on black and white, record its location and the backgrounds where it appears, then check the exact model and seller return window. Pixel-defect thresholds vary by manufacturer, model, defect type, and warranty. A browser color pattern cannot repair a dark subpixel or certify the panel. Avoid pressure, rubbing, or aggressive flashing before documenting the condition; pressure can damage the panel, and flashing patterns are unsuitable for people sensitive to flashing light.