1478629 - The point of DevTools Shape Tool with negative margin disappear on maximize window when zoom out the page to 30%

Status: NEW

(DevTools :: Inspector, defect, P3)

Description

[Timea Zsoldos [:zstimi/tzsoldos], Desktop Release QA]

Attachment: testshape.gif

[Affected versions]: 
Firefox 62.0b11

[Affected platforms]:
Windows 8.1 x64
Mac OS X 10.13 
Ubuntu 18.04 x64.

[Steps to reproduce]:
1. Go to about:config and set "layout.css.shape-outside.enabled" to true.
2. Go to http://labs.jensimmons.com/2016/examples/shapes-3.html
3. Maximize the browser window
4. Right click on the image and then click on "Inspect Element".
5. Click on the button displayed next to shape-outside to toggle the shape tool on.
6. Change the img-margin to a negative value (ex: -3)
7. Drag a point outside the page, from left to right side of the window, near by vertical scroll.
8. Zoom in and zoom out the page to 30%.

[Expected result]:
- The point from the rightmost of the page not disappear and can be moved back.

[Actual result]:
- The point from the rightmost of the page goes outside the page and cannot be moved back, because the horizontal scroll disappear.

[Note]:
This issue happens only in maximize window, because in minimize window the horizontal scroll not disappear.