Page Optimize

Harden CSS concat @import hoisting to preserve long Google Fonts-style URLs with semicolons and avoid false positives from @import-like substrings in rule bodies/URL paths.

Skip JavaScript concatenation for scripts that request defer or async loading to preserve core loading behavior.

Skip JavaScript concatenation for module scripts (type=”module”) and scripts whose tag is modified via the script_loader_tag filter (for example, plugins that add module attributes), improving compatibility.

Preserve stylesheet enqueue/document order when concatenating CSS. Concat-eligible styles are now emitted as sequential runs and split around non-concatenated items (e.g. external/excluded/dynamic URLs), media changes, RTL handling, and other boundaries.

Inline styles (wp_add_inline_style) now print immediately after their parent stylesheet, including when styles are concatenated.

Apply core’s style_loader_tag filter when a concatenation run contains only a single stylesheet (matching core behavior and the JS-side fix from 0.5.0).

The css_do_concat filter is now evaluated once per handle.

The concat service no longer drops @import directives due to a closure scoping bug. (@charset/@import handling now runs against the intended pre-output buffer.)

Stylesheets containing @import now start a new concat run so service-side @import hoisting cannot reorder imports ahead of earlier stylesheets.

Treat @import and @charset as case‑insensitive when building concatenated CSS, preventing missed rules in some stylesheets.