Why isn't this symbol stainer tool working on this symbol?

Question

I've created a symbol in Illustrator with default settings. Here's how I made the object for symbol:

1. A rectangle with white color - Changed its opacity to 20%
2. Inside the rectangle, there are circles with black background (It's like a password input field) and opacity is changed to around 20%
3. Then I grouped all these things and put it in symbol panel to make a symbol
4. Then I locked and hide it in layer panel.
5. Now I created fresh symbols of this type. This is fine.

Here's the image:

The problem is that Symbol stainer tool is not working (or may be working I can't see effect). The color is not changing at all. Is it because of Lock/Opacity/Hide of original grouped object?

Answer 1

The Symbol Stainer tool only changes the hue of a symbol, so black and white objects obviously aren't visibly affected.

From Illustrator Help / Symbolism tools and symbol sets:

Staining a symbol instance changes the hue toward the tint color, while preserving the original luminosity. (It works in the same way as the Tints and Shades colorization method of tinting brushes.) This method uses the luminosity of the original color and the hue of the colorization color to generate the resulting color. Consequently, colors with very high or very low luminosity change very little; black or white objects don’t change at all.