User reported issue: black lines in background

[oliver-phet]

Test device: Macbook Pro

Operating System:Sierra

Browser:Safari

Problem description:see below

Steps to reproduce:unable to reproduce

Severity:

Screenshots:attached

Troubleshooting information (do not edit):
Name: ‪Area Builder‬
URL: https://phet.colorado.edu/sims/html/area-builder/latest/area-builder_en.html
Version: 1.1.3 2017-01-13 10:55:47 UTC
Features missing: touch
Flags: pixelRatioScaling
User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_12_2) AppleWebKit/602.3.12 (KHTML, like Gecko) Version/10.0.2 Safari/602.3.12
Language: en-us
Window: 1406x779
Pixel Ratio: 2/1
WebGL: WebGL 1.0 (2.1 INTEL-10.22.25)
GLSL: WebGL GLSL ES 1.0 (1.20)
Vendor: WebKit (WebKit WebGL)
Vertex: attribs: 16 varying: 15 uniform: 1024
Texture: size: 16384 imageUnits: 16 (vertex: 16, combined: 16)
Max viewport: 16384x16384
OES_texture_float: true
Dependencies JSON: {"area-builder":{"sha":"e289414f","branch":"HEAD"},"assert":{"sha":"7d27130a","branch":"HEAD"},"axon":{"sha":"5e33541f","branch":"HEAD"},"babel":{"sha":"881873dc","branch":"master"},"brand":{"sha":"bb1cfcc6","branch":"HEAD"},"chipper":{"sha":"e7cd7ef3","branch":"HEAD"},"dot":{"sha":"bf6f038b","branch":"HEAD"},"joist":{"sha":"b1ef6e0a","branch":"HEAD"},"kite":{"sha":"dce9765e","branch":"HEAD"},"phet-core":{"sha":"c48bf320","branch":"HEAD"},"phetcommon":{"sha":"143042d6","branch":"HEAD"},"scenery":{"sha":"9cf56c41","branch":"HEAD"},"scenery-phet":{"sha":"436bf61d","branch":"HEAD"},"sherpa":{"sha":"a7ccb78f","branch":"HEAD"},"sun":{"sha":"9f2d40d5","branch":"HEAD"},"tandem":{"sha":"0ad35fb7","branch":"HEAD"},"vegas":{"sha":"4a245d0d","branch":"HEAD"},"vibe":{"sha":"e6fdee6a","branch":"HEAD"}}

[jbphet]

@phet-steele - can you see if you or one of the QA team members can figure duplicate this and, if so, determine how?

[phet-steele]

I have never in my life made this happen. I'm not going to spend more time on it. Pretty sure it was a fluke and/or machine specific.

[liammulh]

Un-assigning myself since I no longer do QA work.

EDIT: Or not? I guess I can't in-assign myself 🙃

[KatieWoe]

There you go. Not sure why you couldn't do it, but I was able to.