2042667 - Page Down/Up key is ignored inside a TextArea without vertical scroll bar once the host page has vertical scroll bar

Status: RESOLVED DUPLICATE of bug 2052637

(Core :: Panning and Zooming, defect)

Description

[Marius Dumitru Florea]

User Agent: Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:151.0) Gecko/20100101 Firefox/151.0

Steps to reproduce:

Take for instance this basic HTML page:

<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8">
<title>Test Page Down/Up in TextArea</title>
</head>
<body>
<div>
<textarea style="height:300px">
1

2

3

4

5

6

7

8

9

10
</textarea>
<p style="height:600px; border: 1px solid">Content after</p>
</div>
</body>
</html>

Save this and open with Firefox. I noticed this inconsistent behavior:

• when the host page doesn't have a vertical scroll bar and neither the textarea => Page Down / Up keys work as expected
• when the host page has a vertical scroll bar (resize the textarea to force a scrollbar on the host page) but the textarea doesn't have it => the Page Down / Up keys stop working (they are simply ignored)
• when the host page doesn't have a vertical scroll bar but the textarea has it (just add more content to the textarea) => the Page Down / Up keys work as expected
• when both the host page and the textarea have a vertical scrollbar => the Page Down / Up keys work as expected

Actual results:

If it wasn't clear enough, here's a simplified table with the outcome:

| | Page with scrollbar | Page without scrollbar |
| TextArea with scrollbar | OK | OK |
| TextArea without scrollbar | FAIL | OK |

Expected results:

I believe the behavior of the same textarea instance should be consistent and shouldn't be affected by the content before / after or whether the host page has scrollbar or not. For the record, Chrome's behavior in this case is consistent.

Note that my real use case is a textarea with auto-height (its height increases with the typed content). The user starts with a small text area (and the host page has no scroll bars), in which case the Page Down / Up work as expected, then they add content, causing the height of the text area to increase. At some point the increase of the textarea height causes the host page to get vertical scrollbar at which point the Page Down / Up keys stop working...

Comment 1

[Marius Dumitru Florea]

I haven't mentioned, but this used to work fine up until recently (149.0.2 was fine AFAIK). So this is a regression introduced in 150 or 151.

Comment 2

[BugBot [:suhaib / :marco]]

The Bugbug bot thinks this bug should belong to the 'Core::Panning and Zooming' component, and is moving the bug to that component. Please correct in case you think the bot is wrong.

Comment 3

[BugBot [:suhaib / :marco]]

The severity field is not set for this bug.
:botond, could you have a look please?

For more information, please visit BugBot documentation.

Comment 4

[Marius Dumitru Florea]

Are there any plans to address this issue? Thanks!

Comment 5

[Botond Ballo [:botond]]

Alex, could you triage this issue please so that we can identify next steps?

Comment 6

[6k64x4ma]

I'm sorry, I overlooked this and submitted a duplicate bug 2052637.

Comment 7

[Botond Ballo [:botond]]

(In reply to 6k64x4ma from comment #6)

I'm sorry, I overlooked this and submitted a duplicate bug 2052637.

Ah, thanks!