[FR]: pastel color support in tab group

[shekhtonce]

Description

the colors that I can pick is too strong now. I prefer pastel colors or colors slightly transparent

Who's implementing?

• I'm willing to implement this feature myself

The problem

the strong tab color broke the overall UI/UX in the browser.

Possible solutions

add transparent to the colors for tab group (or even for themes too)

Additional context

No response