private void addIconToCache(Color color) { if (_iconCache.ContainsKey(color)) { return; } Bitmap imageWithoutBorder = WinFormsHelpers.ReplaceColorInBitmap( Properties.Resources.gitlab_icon_stub_16x16, Color.Green, color); Icon iconWithoutBorder = WinFormsHelpers.ConvertToIco(imageWithoutBorder, 16); Bitmap imageWithBorder = WinFormsHelpers.ReplaceColorInBitmap( Properties.Resources.gitlab_icon_stub_16x16_border, Color.Green, color); Icon iconWithBorder = WinFormsHelpers.ConvertToIco(imageWithBorder, 16); _iconCache.Add(color, new IconGroup(iconWithoutBorder, iconWithBorder)); }