IconToolkit [Web Edition] - Workspace
Smart Secondary (Auto)

AutoGlow v2 - Supersampled (Recommended)

Please try out Glow v2 first, and if you don't get the desired results, check out v1!
v1 is mainly designed for very specific cases, like icons with sharp spikes, which v2 would fail to deliver smooth glow on.

Palette
Live Preview

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Sec. Mapper Workspace
Detected Internal Regions:

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