Button icon licensing issues

[jonathanolson]

We're advertising scenery-phet as MIT licensed, which means we can't use font-awesome 5 icons (which are CC-By licensed, explicitly noted at https://github.com/phetsims/sherpa/blob/main/licenses/fontawesome-free-5.15.2-desktop.txt#L8).

It looks like we have licensing issues with:

• CameraButton
• CanvasWarningNode
• ClapperboardButton
• ContextLossFailureDialog
• EyeToggleButton
• InfoButton
• MoveToTrashButton
• RefreshButton
• SoundToggleButton
• TrashButton

It looks like a lot of these conversions happened as part of phetsims/sherpa#83. I'm including @samreid.

So we can either:

1. Remove font-awesome 5 content from scenery-phet (maybe a repo for sim-licensed things?)
2. Change scenery-phet's license (but there's a LOT of content we want MIT licensed in here. If we change the license, we'd need to move a bunch of content and potentially phet-specific stuff to sun (or some new repository in the "middle", e.g. "MIT licensed but not general UI components like Sun"
3. Undo the conversion to FA-5 that we did earlier.

Thoughts?

[jonathanolson]

Also including @brettfiedler, since if we have things using font-awesome 5 icons, they can't be included in scenery-stack.

[jonathanolson]

This is also blocking any THREE.js integration (mobius now uses a FA-5 icon with phetsims/mobius@ffad97db).

[jonathanolson]

Unblocked by adding FA-4 warning sign back.

[samreid]

It seems preferable to avoid licensing encumbrances for scenery-stack, so I agree we should avoid FA-5 there.

Font Awesome 4 is licensed as SIL OFL 1.1 https://fontawesome.com/v4/license/, which does not require attribution (though outside of the license text, the author said attribution is not required but much appreciated.

Where the icons look similar, it seems safe to go back to FA-4. We kept a few FA-4 things around in sherpa anyways (checkEmptySolidShape, checkSquareOSolidShape, scissorsShape).

We can also consider open source MIT licensed icons libraries such as https://heroicons.com/ which look nice.

[pixelzoom]

Unassigning myself. PixelZoom does not provide legal advice or consulting on licensing.