The frame stays put; only the content cross-fades. Manual only. Hover for the tiny chevrons (100ms fade). Dots are the sole "there's more" cue — small, low-contrast, active is ~2× width (no big pill).
Now driven four ways. Swipe (two-finger trackpad / Magic Mouse — one step per gesture), chevrons (tall invisible edge-strip hit areas, so you don't have to spear a 12px icon), dots (17px hit target around the 5px dot), and arrow keys. The dots are really just the indicator — chevrons + swipe are the reliable navigation, which is why their poor click-targetness doesn't matter much. VoiceOver would get an adjustable action. Content cross-fades in place; toggle reduce-motion for instant.