Both generated from the RangerHQ helmet logo + Arial typography on the
extension's own #0f1411 dark palette so the Dashboard preview blends
naturally with the screenshots.
- promo-tile-440x280.png: helmet anchor left, "RangerHQ Tuner" cream
bold + "Indie radio in your toolbar" accent green + "SomaFM · No
telemetry · GPL v2+" muted footer. Web Store requires this size for
search/browse listing tile.
- marquee-1400x560.png: same idea scaled up. Optional asset; Google
promotes extensions with marquees more often.
ImageMagick recipe documented in store/screenshots/README.md.