Symptom
BoltAudit's CDN probe shows that asset URLs like /wp-includes/css/dist/block-library/style.min.css?ver=6.4 are getting cache-control: no-cache or x-cache: MISS at the edge.
Impact
- Asset URLs change every WP minor version, busting browser AND CDN caches for everyone.
- Bigger problem on hosts with strict-query-string cache rules.
- A non-issue on Cloudflare (it caches with query strings if you tell it to) — biggest impact on shared/legacy CDNs.
Manual fix
Add to your theme's functions.php (or a small custom plugin):
CODE0
Apply Fix
One-click in the dashboard. The fix drops a small must-use plugin that applies the filter above, so it survives theme switches.
Trade-off
Removing ?ver= removes WordPress's built-in cache-busting on plugin/theme updates. New deploys of the same plugin won't evict the old asset from the browser cache automatically. Combine this fix with a deploy-time CDN purge to compensate.
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