{"id":119896,"date":"2025-10-07T08:00:00","date_gmt":"2025-10-07T01:00:00","guid":{"rendered":"https:\/\/tino.vn\/blog\/?p=119896"},"modified":"2026-01-02T17:03:42","modified_gmt":"2026-01-02T10:03:42","slug":"sua-loi-render-blocking-javascript-and-css","status":"publish","type":"post","link":"https:\/\/tino.vn\/blog\/sua-loi-render-blocking-javascript-and-css\/","title":{"rendered":"C\u00e1ch s\u1eeda l\u1ed7i Render-Blocking JavaScript and CSS trong WordPress [2026]"},"content":{"rendered":"\n

Trong qu\u00e1 tr\u00ecnh v\u1eadn h\u00e0nh website WordPress<\/a>, t\u1ed1c \u0111\u1ed9 t\u1ea3i trang l\u00fac n\u00e0o c\u0169ng \u0111\u00f3ng vai tr\u00f2 quan tr\u1ecdng trong vi\u1ec7c gi\u1eef ch\u00e2n ng\u01b0\u1eddi d\u00f9ng v\u00e0 c\u1ea3i thi\u1ec7n th\u1ee9 h\u1ea1ng SEO<\/a>. Tuy nhi\u00ean, nhi\u1ec1u website th\u01b0\u1eddng m\u1eafc ph\u1ea3i l\u1ed7i “Render-Blocking JavaScript and CSS” \u2014 g\u00e2y ch\u1eadm qu\u00e1 tr\u00ecnh hi\u1ec3n th\u1ecb n\u1ed9i dung ch\u00ednh. V\u1eady l\u1ed7i n\u00e0y l\u00e0 g\u00ec, v\u00ec sao l\u1ea1i x\u1ea3y ra. C\u00f9ng Tino t\u00ecm hi\u1ec3u c\u00e1ch s\u1eeda l\u1ed7i Render-Blocking JavaScript and CSS qua b\u00e0i vi\u1ebft d\u01b0\u1edbi \u0111\u00e2y!<\/strong><\/p>\n\n\n\n

<\/a>L\u1ed7i Render-Blocking JavaScript and CSS l\u00e0 g\u00ec?<\/strong><\/h2>\n\n\n\n

\u0110\u1ecbnh ngh\u0129a l\u1ed7i Render-Blocking JavaScript and CSS<\/strong><\/p>\n\n\n\n

L\u1ed7i “Render-Blocking JavaScript and CSS” x\u1ea3y ra khi c\u00e1c t\u1ec7p JavaScript v\u00e0 CSS tr\u00ean trang web c\u1ee7a b\u1ea1n ng\u0103n tr\u00ecnh duy\u1ec7t hi\u1ec3n th\u1ecb n\u1ed9i dung trang m\u1ed9t c\u00e1ch nhanh ch\u00f3ng, d\u1eabn \u0111\u1ebfn l\u00e0m ch\u1eadm qu\u00e1 tr\u00ecnh t\u1ea3i trang.<\/p>\n\n\n\n

Khi ng\u01b0\u1eddi d\u00f9ng truy c\u1eadp v\u00e0o m\u1ed9t trang web, tr\u00ecnh duy\u1ec7t c\u1ea7n t\u1ea3i v\u00e0 x\u1eed l\u00fd t\u1ea5t c\u1ea3 m\u00e3 HTML, CSS v\u00e0 JavaScript tr\u01b0\u1edbc khi c\u00f3 th\u1ec3 hi\u1ec3n th\u1ecb n\u1ed9i dung ho\u00e0n ch\u1ec9nh. Tuy nhi\u00ean, n\u1ebfu c\u00e1c t\u1ec7p CSS ho\u1eb7c JavaScript kh\u00f4ng \u0111\u01b0\u1ee3c t\u1ed1i \u01b0u h\u00f3a ho\u1eb7c \u0111\u01b0\u1ee3c \u0111\u1eb7t \u1edf ph\u1ea7n \u0111\u1ea7u (header) c\u1ee7a trang m\u00e0 kh\u00f4ng s\u1eed d\u1ee5ng k\u1ef9 thu\u1eadt t\u1ea3i b\u1ea5t \u0111\u1ed3ng b\u1ed9 (async) ho\u1eb7c tr\u00ec ho\u00e3n (defer), ch\u00fang s\u1ebd “ch\u1eb7n” quy tr\u00ecnh hi\u1ec3n th\u1ecb (rendering) cho \u0111\u1ebfn khi ch\u00fang \u0111\u01b0\u1ee3c t\u1ea3i xong.<\/p>\n\n\n

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\"L\u1ed7i
L\u1ed7i Render-Blocking JavaScript and CSS l\u00e0 g\u00ec?<\/strong><\/strong><\/figcaption><\/figure>\n<\/div>\n\n\n

\u0110i\u1ec1u n\u00e0y khi\u1ebfn ng\u01b0\u1eddi d\u00f9ng ph\u1ea3i ch\u1edd l\u00e2u h\u01a1n \u0111\u1ec3 nh\u00ecn th\u1ea5y n\u1ed9i dung ch\u00ednh c\u1ee7a trang, g\u00e2y \u1ea3nh h\u01b0\u1edfng ti\u00eau c\u1ef1c \u0111\u1ebfn tr\u1ea3i nghi\u1ec7m ng\u01b0\u1eddi d\u00f9ng c\u0169ng nh\u01b0 \u0111i\u1ec3m s\u1ed1 hi\u1ec7u su\u1ea5t trang trong c\u00e1c c\u00f4ng c\u1ee5 \u0111\u00e1nh gi\u00e1 nh\u01b0 Google PageSpeed Insights.<\/p>\n\n\n\n

<\/a>C\u00e1c nguy\u00ean nh\u00e2n ph\u1ed5 bi\u1ebfn g\u00e2y ra l\u1ed7i “Render-Blocking JavaScript and CSS”<\/strong><\/h3>\n\n\n\n

<\/a>JavaScript v\u00e0 CSS \u0111\u01b0\u1ee3c t\u1ea3i \u0111\u1ed3ng b\u1ed9 <\/h4>\n\n\n\n

M\u1eb7c \u0111\u1ecbnh, tr\u00ecnh duy\u1ec7t s\u1ebd \u0111\u1ecdc v\u00e0 t\u1ea3i t\u1eebng t\u00e0i nguy\u00ean theo th\u1ee9 t\u1ef1 t\u1eeb tr\u00ean xu\u1ed1ng. Khi g\u1eb7p file JavaScript ho\u1eb7c CSS trong <head> ho\u1eb7c <body>, tr\u00ecnh duy\u1ec7t s\u1ebd d\u1eebng render n\u1ed9i dung cho \u0111\u1ebfn khi t\u1ea3i v\u00e0 th\u1ef1c thi xong c\u00e1c file n\u00e0y.<\/p>\n\n\n\n

<\/a>CSS v\u00e0 JavaScript kh\u00f4ng c\u1ea7n thi\u1ebft \u0111\u01b0\u1ee3c t\u1ea3i s\u1edbm h\u01a1n<\/h4>\n\n\n\n

M\u1ed9t s\u1ed1 file CSS d\u00f9ng \u0111\u1ec3 \u0111\u1ecbnh d\u1ea1ng ph\u1ea7n kh\u00f4ng hi\u1ec3n th\u1ecb ngay l\u1eadp t\u1ee9c (footer, popup, widget…) nh\u01b0ng v\u1eabn \u0111\u01b0\u1ee3c t\u1ea3i t\u1eeb \u0111\u1ea7u. \u0110i\u1ec1u n\u00e0y khi\u1ebfn tr\u00ecnh duy\u1ec7t ph\u1ea3i x\u1eed l\u00fd c\u1ea3 nh\u1eefng t\u00e0i nguy\u00ean ch\u01b0a c\u1ea7n thi\u1ebft, g\u00e2y ch\u1eadm qu\u00e1 tr\u00ecnh render.<\/p>\n\n\n\n

T\u01b0\u01a1ng t\u1ef1 CSS, nhi\u1ec1u \u0111o\u1ea1n m\u00e3 JavaScript kh\u00f4ng c\u1ea7n thi\u1ebft cho n\u1ed9i dung ch\u00ednh nh\u01b0ng l\u1ea1i t\u1ea3i ngay t\u1eeb \u0111\u1ea7u. V\u00ed d\u1ee5 nh\u01b0:<\/p>\n\n\n\n