Mapbox doesn't work if WebGL is unavailable / browser hardware acceleration is disabled.

[romeboards]

Describe the bug We noticed this on https://github.com/JustFixNYC/who-owns-what/pull/49 and the wonderful @sraby identified it on the new ZoLa as well. See the thread for more info...

To Reproduce You can disable WebGL/hardware acceleration on Chrome in Settings > Advanced Settings > Use hardware acceleration when available:

Screenshots If applicable, add screenshots to help explain your problem.

Desktop (please complete the following information):

• OS: [e.g. iOS] Mac 10.12.6
• Browser [e.g. chrome, safari] Chrome
• Version [e.g. 22] 70.0.3538.67 (Official Build) (64-bit)

[allthesignals]

Thanks @romeboards! We should add some handling for users who have MapboxGL disabled. We could explain that it's required to use ZoLa. It's a bit theoretical, but we could also "gracefully degrade" by falling back to LeafletJS which doesn't require WebGL.