Projection mode makes reading tape measure difficult

[KatieWoe]

Test device
Dell
Operating System
Win 10
Browser
Chrome
Problem description
For phetsims/qa#505. Does not occur in published version
If you put the sim in projection mode (turning the background white) and pull out the tape measure, the text reading out the measurement is difficult or almost impossible to read. It is black text in a black bubble. In the published version it is black text on a white background.

Visuals

Here is the published version to compare:

Troubleshooting information:

!!!!! DO NOT EDIT !!!!!
Name: ‪Gravity and Orbits‬
URL: https://phet-dev.colorado.edu/html/gravity-and-orbits/1.2.0-dev.10/phet/gravity-and-orbits_en_phet.html
Version: 1.2.0-dev.10 2020-05-26 17:36:54 UTC
Features missing: touch
Flags: pixelRatioScaling
User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/83.0.4103.61 Safari/537.36
Language: en-US
Window: 1536x722
Pixel Ratio: 2.5/1
WebGL: WebGL 1.0 (OpenGL ES 2.0 Chromium)
GLSL: WebGL GLSL ES 1.0 (OpenGL ES GLSL ES 1.0 Chromium)
Vendor: WebKit (WebKit WebGL)
Vertex: attribs: 16 varying: 30 uniform: 4096
Texture: size: 16384 imageUnits: 16 (vertex: 16, combined: 32)
Max viewport: 32767x32767
OES_texture_float: true
Dependencies JSON: {}

[KatieWoe]

Note that this does not seem to happen with the similar mass labels.

[samreid]

In discussion with @arouinfar we agreed this seems straightforward to fix, and it should be done before next dev release.

[samreid]

I'll work on this in #266, thanks!

[samreid]

Addressed in #266, but @KatieWoe can you please verify on phettest? Close if all is well.

[KatieWoe]

Looks good on master