Support alpha in Hex for color picker

I was working with react-color and found some issues about the alpha color, I manage to solve them by converting rgba to hex. and found that hex values don't support alpha values.
I mean a hex value support 6 characters for RGB but some software and in CSS hex value can have 8 characters with the last 2 characters are for the alpha value.
it would be useful to have an auto-convert from RGBA to HEX without losing the alpha value.

No file or test is named in the issue. Start by locating the color conversion and picker formatting paths in react-color, then trace how RGBA values become hexadecimal output. Done means alpha is preserved in an 8-character hex value, with tests covering conversion from RGBA without losing transparency.

Written by the indexing model from the issue text.