Sonic 3&K Angel Island (Dark)
I really liked this extension: https://addons.mozilla.org/en-GB/firefox/addon/sonic-3-knuckles-angel-island
But, the colours were too bright for me. So this extension slightly darkens the image, as well as using darker colours.
Easier on your eyes!
Sonic 3&K Angel Island (Dark)
Add-on stats
Weekly download count: 8
Firefox on Android: No
Risk impact: Very low risk impact 
Risk likelihood:
Manifest version: 2
Size: 35.26K
Other platforms
Not available on Chrome
Not available on Android
Not available on Edge
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Add-on safety
Risk impact
Sonic 3&K Angel Island (Dark) does not require any sensitive permissions.
Risk likelihood
Sonic 3&K Angel Island (Dark) is probably trust-worthy. Prefer other publishers if available. Exercise caution when installing this add-on.
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