Fluorescent documents its themes well, so the paid work clusters around updates and code rather than settings.
Manual updates with custom code. Automated updates keep theme editor customizations but not custom code, and support doesn't cover manual updates. Fluorescent's own method copies templates, the header, footer and overlay section groups, and settings_data.json into the new version, then previews both side by side.
The jump to version 6. Fluorescent reports an ongoing Shopify auto-update issue for versions older than 6. Afterward, color schemes must be rebuilt, because Shopify doesn't carry older colors across. Stiletto reached 6.2.0 on September 1, 2026.
Navigation and swatches. Stiletto's help center covers mega navigation and variant swatches built from default colors, custom images or custom colors. Across a large variant catalog, that setup is slow work.
Cornerstone for big catalogs. Cornerstone is marketed for large catalogs and high SKU volumes, with B2B support across sales channels, predictive search and swatch filters to configure.
Code that stays maintainable. The themes ship with custom events, custom Liquid sections and editable JavaScript with a classic build file. A developer should build on those hooks rather than core files.
Content by market and language. The help center covers unique content for markets and selling in multiple languages. Our Shopify Markets guide covers the platform side.
Bugs on an unmodified theme. Those go to Fluorescent's support, free.