Add more visual hints that a project is a fork
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I've been chatting with @annabeldunstone about the upcoming improvements we have for forking. Have we considered overlaying a fork-related glyph, pill, or _some_ kind of visual element on the main page for a repo when it's a fork? Here's an example of my personal fork (https://gitlab.com/aqualls/gitlab) of the `gitlab` repo:

Every time I need to test something on my fork, I have a moment of panic: _am I absolutely certain I'm not about to do something destructive on the main `gitlab` repo?_ Aside from the one little box that says `Forked from GitLab.org / GitLab`, everything's the same: the icon, the project name …
I make this issue because the life I save may be my own.
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