Feature request: Allow alpha channel for colours

[mattyp]

When selecting colours, I don't have an option for transparency (alpha channel). Is that easy enough to add in?

[TheJoeFin]

This should be fairly easy to enable on the color picker side, but I will have to look into if the QR Code image outputs work correctly with the addition of the alpha channel

[mattyp]

Even a simple checkbox to toggle transparent for each colour, rather than an alpha channel would be helpful. Alpha channel does give more options though.