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Tailwind CSSNext.jsMigration

Tailwind v4: Icons Not Showing After Upgrade? bg-opacity-* Was Removed

Upgraded to Tailwind CSS v4 and your icons vanished, overlays went opaque, or tinted backgrounds turned solid? The bg-opacity-* utilities were removed in v4, the official upgrade tool doesn't rewrite them, and they fail without a single build error. Here's how to find every instance and fix it safely.

July 27, 2026

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