Hello,
I built and used my own theme by years. Then almost one month ago, firefox request new theme. So I designed new one. However my friends and society request to change it. Because of it’s color. Finaly I fixed the color and change the background image. BUT it is rejected. I design it to use and my friends wants to use but it is rejected. It’s link is below. Please allow to use it.
https://addons.mozilla.org/en-US/developers/addon/lordtek-berke-v2-0
Sincerely.
Hi @LORDTEK, thanks for reaching out! It looks like you might have accidentally uploaded the same theme twice. This submission was approved and the other was rejected for being a duplicate.
Tell all your friends to go to the URL of the approved version and install your theme! 
There is not duplication. They were different themes. What you did is not good.
how is this even a solution? The user says it is different. There are very popular themes from the same users with the only difference one highlight color, and it makes sense since this is the point of customization. So why don’t you let us create variations any more? I have created a variation of a theme and get the same message.