HTML/DOM team biweekly snippet (Nov. 21 - Dec. 4)

[Takayoshi Kochi]

The HTML/DOM team is located at Google Tokyo to work on Blink, especially

focusing on HTML/DOM interoperability, Web Components, and Editing.

Updates for last 2 weeks (on Monday, Dec. 4, 2016):

P1 Bug Fixit

  We had a Fixit event for three days, and fixed 12 P1 bugs in our areas.

Zero interoperability bugs

- Fix interoperability issues:

  - Implemented ::placeholder pseudo element (tkent)

  - Removed the wrong optimization in replacing a text node with innerHTML (hayato)

- Import more WPT tests: imported wpt/domparsing/, wpt/domxpath/, and wpt/innerText/ (tkent)

Shadow DOM code health / bug fixes

- Intent to Deprecate: Shadow DOM v0 (hayato)

  - The next actions are: 

   (1) We will not deprecate Shadow DOM v0 unless we have a clear (hopefully)

        evidence for what caused the high usage number.

   (2) File issues / PRs to switch to ShadowDOMv1 for AdBlock Plus / AdBlock.

   (3) In addition to that, try other ways to figure out the cause, as you suggested.

- Stop a SVG <use> element from modifying its UA shadow tree when it is removed;

  Fixes a UXSS issue (hayato)

Pipeline friendly editing

- Revising design doc of Idle time spell checking and prototyping (xiaochengh)

- Tried to ensure clean style for hasEditableStyle and then hoist style update calls;

  Was blocked and needs to discuss the future of -webkit-user-modify (xiaochengh, yoichio, yosin)

- Defer visible selection canonicalization to make selection pipeline friendly;

  incrementally committing the code (yosin)

- Introducing SynchronousMutationObserver for Blink C++ classes who hold DOM nodes to

  avoid using disconnected nodes for consistency and no memory leak (yosin)