v150 · HTML · Navigation

Fragment Tester

Three anchors use the same base name with different cases: name="section", name="Section", and name="SECTION". Click a fragment link and compare the active standards-mode document with a real no-doctype quirks-mode iframe. Chrome 150+ should only target the exact-case anchor in both documents.

Detecting Chrome version...

Standards-mode anchor targets on this page

Navigate to a fragment. The same fragment is applied to this page and to the quirks-mode iframe.

Standards document target Waiting for fragment...
Quirks iframe target Waiting for iframe...
fragment standards actual quirks iframe actual Chrome 150+ expected

Standards mode vs real quirks mode

Active document
doctype: <!doctype html>
compatMode: -
fragment source: -
matching rule: case-sensitive name lookup
Embedded quirks document
doctype: none
compatMode: loading...
expected Chrome 150+: exact-case name lookup

How this page tests quirks mode

// The iframe document is written with <html>, not <!doctype html>.
// That makes iframe.contentDocument.compatMode report "BackCompat".

iframe.contentWindow.location.hash = "Section";
const target = iframe.contentDocument.querySelector(":target");

// Chrome 150+: target.getAttribute("name") === "Section"
// Earlier Chrome quirks mode could match name="section" first.