mongol-3.0.1/lib/src/button/mongol_icon_button.dart:151:25: Error: Operator '+' cannot be called on 'double?' because it is potentially null.
(iconSize + math.min(padding.horizontal, padding.vertical)) * 0.7,
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mongol-3.0.1/lib/src/button/mongol_icon_button.dart:151:25: Error: Operator '+' cannot be called on 'double?' because it is potentially null. (iconSize + math.min(padding.horizontal, padding.vertical)) * 0.7,