Open Bug 1318340 Opened 7 years ago Updated 1 year ago

Changing the viewport size from the grippers is not smooth


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

52 Branch


(firefox50 unaffected, firefox51 unaffected, firefox52 wontfix, firefox53 affected)

Tracking Status
firefox50 --- unaffected
firefox51 --- unaffected
firefox52 --- wontfix
firefox53 --- affected


(Reporter: phorea, Unassigned)


(Blocks 1 open bug)


(Whiteboard: [rdm-v2])


(1 file)

- 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]:

[Additional notes]:
- The window content is also shaking
- While resizing the viewport, the mouse cursor doesn't stick to the grippers
Attached image resizeUnderWin.gif
Attached behavior under Windows 10. Ubuntu looks about the same.
For OS X the behavior is improved.
QA Whiteboard: [qe-rdm]
Whiteboard: [multiviewport] [reserve-rdm] → [rdm-v2][triage]
> Whiteboard: [multiviewport] [reserve-rdm] → [rdm-v2][triage]

Can you help clarify what that means? :) We were wondering during regression triage today.
Flags: needinfo?(jryans)
(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).
Flags: needinfo?(jryans)
Flags: qe-verify+
QA Contact: mihai.boldan
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.
Assignee: nobody → jryans
Keywords: regression
Priority: -- → P2
Whiteboard: [rdm-v2][triage] → [rdm-v2]
Mass wontfix for bugs affecting firefox 52.
Assignee: jryans → nobody
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:

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?
Product: Firefox → DevTools
Blocks: rdm-ux
Severity: normal → S3
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