Bug 29815 – REGRESSION (r48698): Cannot enter text in Facebook message content field

• Component: Evangelism
• Status: RESOLVED WONTFIX

The Message text field in the Facebook Compose Message box does not accept text entry.

Steps to reproduce:
1. Log in to Facebook
2. Choose Inbox > Compose New Message
3. Click in the Message text field
4. Type some text

Result:
No text appears in the Message text field

Regression:
This is a regression from <http://trac.webkit.org/changeset/48698>

<rdar://problem/7258171>

[Kent Tamura]

I have confirmed I couldn't type anything into a textarea.
However, this <textarea> element actually had maxlength="0" according to the inspector.  So, this is an expected behavior and a Facebook's bug.

What should we do in such case?

[Kent Tamura]

> However, this <textarea> element actually had maxlength="0" according to the
> inspector.  So, this is an expected behavior and a Facebook's bug.

It doesn't have maxlength="0" in an HTML text.  The code seems to call "textarea.maxLength = 0" and it makes a maxlength="0" attribute.

[Kent Tamura]

I took a look at a Facebook JS code.
I guess TextInputControl class in it does something like the following:
  textarea.maxLength = textarea.maxLength;

If maxlength= HTML attribute is missing, .maxLength is 0 according to older HTML5 draft, so the new .maxLength becomes 0, of course.

Maybe this bug will be fixed if Bug#29796 is fixed.  I'll check it soon.

[Kent Tamura]

(In reply to comment #4)
> I took a look at a Facebook JS code.
> I guess TextInputControl class in it does something like the following:
>   textarea.maxLength = textarea.maxLength;

My guess was wrong.  Returning -1 for .maxLength didn't help.

[Kent Tamura]

I understand the Facebook code.
In the definition of TextInpuTcontrol.prototype:
    setMaxLength:function(maxlength){
	this.maxLength=maxlength;
	this.getRoot().maxLength=this.maxLength||null;
	return this;
    },

This code is called by UIComposer.prototype.initializeTextarea() like:
    initializeTextarea:function(maxLength,initialHeight){
	new TextAreaControl(this.input)
	.setMaxLength(maxLength)
	.setOriginalHeight(initialHeight)
	.setAutogrow(true)
	.onfocus();
	this.input.onfocus='';
    },
where the maxLength parameter is 0.


>	this.getRoot().maxLength=this.maxLength||null;
this.getRoot() is a <textarea> element.  In the case of maxLength==0, null is set. null is converted to 0.  So textarea.maxLength becomes 0.

[Kent Tamura]

I reported this issue to Facebook.

[Mark Rowe (bdash)]

I just CCd all of the facebook.com folks with Bugzilla accounts on this bug to hopefully get this some attention.  If this requires a fix on the Facebook side it would be nice to get an ETA for the fix.

[Mark Rowe (bdash)]

*** Bug 29922 has been marked as a duplicate of this bug. ***

[Mark Rowe (bdash)]

Created attachment 40410 [details]
Reduction

I've attached a reduction that demonstrates that Facebook is relying on behavior that works in Firefox but is incorrect per the HTML 5 specification.

[Michael]

I want to confirm this bug.  Unable to insert text in response box on facebook's "inbox"

[Ben Mathews]

I've fixed this in our trunk;  the fix will go out on Tuesday afternoon.

[Mark Rowe (bdash)]

Thanks for the info, Ben!

*** Bug 30046 has been marked as a duplicate of this bug. ***

[Mark Rowe (bdash)]

*** Bug 30056 has been marked as a duplicate of this bug. ***

[Mark Rowe (bdash)]

*** Bug 30058 has been marked as a duplicate of this bug. ***

[Kent Tamura]

I confirmed Facebook's code has no problem now.