MutationObserver

Reports changes to the DOM tree (children, attributes, text) as batched records. Specification: dom.spec.whatwg.org/.

Results

Probed on 2026-10-19 with Node.js v22.23.3.

warpdom 0.1.6

✓ Supported

3 of 3 checks work.

Web IDL existence (coverage):

• MutationObserver: interface present; 3 of 3 members present.

⚑ Report a wrong result for warpdom

happy-dom 21.0.3

✓ Supported

3 of 3 checks work.

Web IDL existence (coverage):

• MutationObserver: interface present; 3 of 3 members present.

⚑ Report a wrong result for happy-dom

jsdom 30.1.3

✓ Supported

3 of 3 checks work.

Web IDL existence (coverage):

• MutationObserver: interface present; 3 of 3 members present.

⚑ Report a wrong result for jsdom

linkedom 0.18.13

◐ Partial

2 of 3 checks work.

Web IDL existence (coverage):

• MutationObserver: interface present; 3 of 3 members present.

• takeRecords() returns pending records synchronously and empties the queue.

  • Result: callback calls after takeRecords(): expected 0, got 1

⚑ Report a wrong result for linkedom

Checks

• child-list-async: An appendChild() is reported asynchronously (not during the call) as one "childList" record. (spec)
• attribute-old-value: With attributeOldValue, an attribute change record carries attributeName and oldValue. (spec)
• take-records: takeRecords() returns pending records synchronously and empties the queue. (spec)