Why does the devicon font display correctly locally but fail to render specific icons when served via a production CDN?

When integrating Devicon icons into a web project, developers often report that the icons render as expected during local development but appear missing or fall back to a generic glyph after deployment to a production environment. This discrepancy can arise from differences in how the stylesheet or font files are served, cached, or built, especially when relying on a CDN versus a locally built copy of devicon.min.css.

What factors might cause the icon classes to resolve incorrectly in production, and how does the build process affect the availability of specific font variants when using a CDN versus a locally built stylesheet?