1318340 - Changing the viewport size from the grippers is not smooth

Status: NEW

(DevTools :: Responsive Design Mode, defect, P2)

Description

[Petruta Horea [:phorea], Desktop QA]

[Note]:
- This is a Firefox 48 regression, but the latest builds show a even worse behavior

[Affected versions]:
- 52.0a2 2016-11-17
- 53.0a1 2016-11-17

[Affected platforms]:
- Win 10 64-bit
- Mac OS X 10.11.5
- Ubuntu 14.04 64-bit

[Steps to reproduce]:
1. Make sure that devtools.responsive.html.enabled pref is set to True.
2. Enable RDM tool.
3. Resize the viewport from the grippers displayed on the bottom right corner.

[Expected result]:
- The viewport is correctly resized.

[Actual result]:
- The resize is not smooth. 

[Regression range]:
- https://hg.mozilla.org/mozilla-central/pushloghtml?fromchange=68c0b7d6f16ce5bb023e08050102b5f2fe4aacd8&tochange=8fc46323cee61bddc4c38701d6020379bba5774a

[Additional notes]:
- The window content is also shaking
- While resizing the viewport, the mouse cursor doesn't stick to the grippers

Comment 1

[Petruta Horea [:phorea], Desktop QA]

Attachment: resizeUnderWin.gif

Attached behavior under Windows 10. Ubuntu looks about the same.
For OS X the behavior is improved.

Comment 2

[Andrew Overholt [:overholt]]

> Whiteboard: [multiviewport] [reserve-rdm] → [rdm-v2][triage]

Can you help clarify what that means? :) We were wondering during regression triage today.

Comment 3

[J. Ryan Stinnett [:jryans] (Use needinfo, replies may be slow)]

(In reply to Andrew Overholt [:overholt] from comment #2)
> > Whiteboard: [multiviewport] [reserve-rdm] → [rdm-v2][triage]
> 
> Can you help clarify what that means? :) We were wondering during regression
> triage today.

We've changed project structures a bit, so that's partially the reason this field changed.  Also, I've added it to a triage list to discuss at the next RDM meeting (Nov. 29).

Comment 4

[J. Ryan Stinnett [:jryans] (Use needinfo, replies may be slow)]

Discussed this during RDM triage today.  We'd like to improve this if we can, but it could be hard to do so with the current centered design.  I'm going to experiment with this a bit.

Since the entire UI has been redesigned in 52 (making this more of bug of the new design) and the team feels okay to ship the current behavior if we can't improve it, I'm removing the regression keyword.

Comment 5

[Julien Cristau [:jcristau]]

Mass wontfix for bugs affecting firefox 52.

Comment 6

[Lorenzo Stanco]

Please reconsider and re-assign this bug! The new Responsive Design Mode shakes like crazy when resizing the viewport to test different sizes, see here: https://i.imgur.com/O72k5mE.gif

I bet this "jitter" is because the viewport is now centered in Responsive Design Mode, so every resize also need a position adjustment, which is somehow delayed / throttled. If make it smoother is not possible, it'd be great to have an option to align everything to the left (like it was before).

Is it possible to change the alignment already, using userChrome.css or userContent.css?