1953174 - Copying selected data generates outer HTML into the clipboard

Status: RESOLVED FIXED

(Core :: DOM: Serializers, defect)

Description

[Edgar Chen [:edgar]]

There is a difference on content serialization result between Firefox and Chrome. For example. if you select all content on https://software.hixie.ch/utilities/js/live-dom-viewer/?saved=13533 and press Ctrl+C, then check the clipboard content:

The data that Firefox put into clipboard:

<div>
  <span>First Line</span>
  <div>
    <span>Second Line</span>
  </div>
  <span>Third Line</span>
</div>

The data the Chrome put into clipboard:

<meta charset='utf-8'><span style="color: rgb(0, 0, 0); font-family: Times; font-size: medium; font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; orphans: 2; text-align: start; text-indent: 0px; text-transform: none; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; white-space: normal; text-decoration-thickness: initial; text-decoration-style: initial; text-decoration-color: initial;">First Line</span><span style="color: rgb(0, 0, 0); font-family: Times; font-size: medium; font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; orphans: 2; text-align: start; text-indent: 0px; text-transform: none; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; white-space: normal; text-decoration-thickness: initial; text-decoration-style: initial; text-decoration-color: initial; display: inline !important; float: none;"></span><div style="color: rgb(0, 0, 0); font-family: Times; font-size: medium; font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; orphans: 2; text-align: start; text-indent: 0px; text-transform: none; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; white-space: normal; text-decoration-thickness: initial; text-decoration-style: initial; text-decoration-color: initial;"><span>Second Line</span></div><span style="color: rgb(0, 0, 0); font-family: Times; font-size: medium; font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; orphans: 2; text-align: start; text-indent: 0px; text-transform: none; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; white-space: normal; text-decoration-thickness: initial; text-decoration-style: initial; text-decoration-color: initial;">Third Line</span>

A key difference is that Firefox includes the outer <div>, whereas Chrome does not. I think this is https://github.com/w3c/clipboard-apis/issues/49 where spec is verge about it.

Comment 1

[Simon Pieters [:zcorpan]]

Per discussion with the Editing WG, we should try to match the behavior of Chromium and WebKit here.

Comment 2

[Masayuki Nakano [:masayuki] (he/him)(JST, +0900)]

Is this caused by the difference of the serializers? I wonder if the other browsers might shrink the selection range when "Select All" to first/last meaningful leaf node start/end. Actually, I got the following range when I do "Select All" on Chrome.

Range {commonAncestorContainer: div, startContainer: text, startOffset: 0, endContainer: text, endOffset: 10, …}
collapsed: false
commonAncestorContainer: div
endContainer: text
endOffset: 10
startContainer: text
startOffset: 0

Comment 3

[Edgar Chen [:edgar]]

"Select All" is a different case. This case is about select all text manually by mouse.
Chrome and us both has same range as below,

Range { commonAncestorContainer: div, startContainer: #text, startOffset: 0, endContainer: #text, endOffset: 10, collapsed: false }
​collapsed: false
​commonAncestorContainer: <div>
​endContainer: #text "Third Line"
​endOffset: 10
​startContainer: #text "First Line"
​startOffset: 0

And our serialized html content for clipboard copying includes the common ancestor element, whereas Chrome doesn't.

Comment 4

[Masayuki Nakano [:masayuki] (he/him)(JST, +0900)]

Oh, thank you for clarifying.

And it seems that this bug is more important on Android. I've not realized that I'm a victim of this bug. When I copy all text in a heading element on Firefox for Android and paste it to another Android app, the pasted text ends with 2 line breaks. I guess the outer heading element of the text in clipboard causes the trailing line breaks when it's pasted into another app's text field. (Although I'm not familiar with clipboard handling/API of Android.)

Comment 5

[Edgar Chen [:edgar]]

(In reply to Masayuki Nakano [:masayuki] (he/him)(JST, +0900) from comment #4)

When I copy all text in a heading element on Firefox for Android and paste it to another Android app, the pasted text ends with 2 line breaks. I guess the outer heading element of the text in clipboard causes the trailing line breaks when it's pasted into another app's text field. (Although I'm not familiar with clipboard handling/API of Android.)

Would you mind filing a separated bug with STR? I could take a look and do some investigation. Thanks!

Comment 6

[Masayuki Nakano [:masayuki] (he/him)(JST, +0900)]

Filed bug 2003716.

Comment 7

[Edgar Chen [:edgar]]

https://treeherder.mozilla.org/jobs?repo=try&landoCommitID=169164

Comment 8

[Edgar Chen [:edgar]]

Attachment: Bug 1953174 - Part 2: Stop always including common ancestor when serializing HTML data for clipboard copy; r?masayuki

Comment 9

[Edgar Chen [:edgar]]

https://treeherder.mozilla.org/jobs?repo=try&landoCommitID=169423

Comment 10

[Edgar Chen [:edgar]]

Attachment: Bug 1953174 - Part 1: Add more mochitest tests for HTMLCopyEncoder; r?masayuki

Comment 11

[Pulsebot]

Pushed by [e-mail]:
https://github.com/mozilla-firefox/firefox/commit/942ef4cb8ece
https://hg.mozilla.org/integration/autoland/rev/2c3c9a4f5113
Part 1: Add more mochitest tests for HTMLCopyEncoder; r=masayuki DONTBUILD
https://github.com/mozilla-firefox/firefox/commit/f244579d668e
https://hg.mozilla.org/integration/autoland/rev/8eba4813d61a
Part 2: Stop always including common ancestor when serializing HTML data for clipboard copy; r=masayuki DONTBUILD

Comment 12

[Cosmin Sabou [:CosminS]]

https://hg.mozilla.org/mozilla-central/rev/2c3c9a4f5113
https://hg.mozilla.org/mozilla-central/rev/8eba4813d61a