What Is a Keystroke Overlay?

A keystroke overlay is a composited visual element that lives above the screen content layer in a recording. "Overlay" implies layering: the screen content is the base layer, and the keystroke badges are drawn on top without replacing or obscuring the underlying UI. This compositing happens either in real time during recording (where the badges appear in the live capture) or in post-production via a plugin or filter. Real-time overlays have the advantage of frame-accurate synchronization; post-production overlays allow more visual customization but require additional editing work.

The design of a keystroke overlay affects both readability and aesthetics. Common design choices include: semi-transparent dark pill backgrounds (which contrast well against both light and dark screen content); white or light-colored key labels (readable against the dark background); subtle fade-in/fade-out animations (which draw the eye without startling the viewer); and positioning in the lower-center or lower-right corner of the frame (where it is noticeable but out of the way of primary UI content). Position should be customizable because different recordings have important content in different screen areas.

Limelight renders its keystroke overlay (activated with ⌃⌥2) as part of the recording pipeline, baking the key badges into the video frame at export time. The overlay uses macOS-native key symbols and a clean, minimal badge style that blends with the look of macOS interfaces. Because it is baked in at export, the overlay requires no post-processing and is visible in every playback context — embedded in web pages, opened in media players, or shared via messaging apps — without the viewer needing any special player or extension.