1549414 - "Scroll into view" logic isn't triggered when dragging the caret past the edge of the viewport after zooming in using Fenix

Status: NEW

(Core :: Panning and Zooming, defect, P3)

Description

[csheany]

User Agent: Mozilla/5.0 (Android 7.1.1; Tablet; rv:68.0) Gecko/68.0 Firefox/68.0

Steps to reproduce:

1. Open this bug
2. Scroll to the description
3. Zoom in
4. Long press (this) word
5. Drag the caret up past the toolbar

Actual results:

The page doesn't scroll

Expected results:

The page does scroll

Comment 1

[Botond Ballo [:botond]]

This used to be broken even when not zoomed in; that was fixed in bug 1404854. It looks like it's never worked when zoomed in.

Comment 2

[csheany]

But it should?

Did I get the summary right?

Comment 3

[Stefan Deiac]

Hello, thanks for your ticket.
I can confirm that your issue is reproducible with this page but not with Wikipedia or Amazon.
Devices:

• Nokia 6 (Android 7.1.1);

Build:

• Release 66.0.4;
• Nightly 68.0a1 (2019-05-06);

It seems that this problem occurs only with some pages. Also on Chrome, I can't reproduce this problem on the same site but it seems that the scroll just jumps very far from the last zone.

Comment 4

[Botond Ballo [:botond]]

(In reply to csheany from comment #2)

But it should?

Yep.

Did I get the summary right?

Pretty good, yeah. I edited it to mention dragging the caret, as that's one of several things that can trigger "scroll into view" logic. (Another example would be typing characters into a text field, as in bug 1545096.)

Comment 5

[BugBot [:suhaib / :marco/ :calixte]]

The priority flag is not set for this bug.
:st3fan, could you have a look please?

For more information, please visit auto_nag documentation.

Comment 6

[Stefan Arentz | :st3fan | ⏰ EST | he/him]

Asking the GV team for triage.

Comment 7

[Chris Peterson [:cpeterson]]

Clearing priority so GV team will see this bug during triage.

Comment 8

[Chris Peterson [:cpeterson]]

Moving to APZ component because this looks like an APZ scrolling issue

Comment 9

[BugBot [:suhaib / :marco/ :calixte]]

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

For more information, please visit auto_nag documentation.

Comment 10

[Botond Ballo [:botond]]

P3 based on comment 1 (not a regression, this is something that has never worked).

Comment 11

[Botond Ballo [:botond]]

Also updating the title to clarify that this bug is about continuing to drag when the finger reaches the end of the viewport.

Comment 12

[Botond Ballo [:botond]]

My recollection is, when I briefly debugged the AccessibleCaret code to understand why this is happening, is that when the finger reaches the end of the viewport, the events don't even make it to AccessibleCaret because their coordinates are out of bounds.

The first step to fixing this would be understanding how this works when not zoomed in.