show shorthand if a item has

[zhangenming]

• please tag the issue title with the spec's shortname, like [css-foo]
  (this is the name from the spec URL, without a level number unless the issue is specific to that level).
  If you're proposing a new feature that doesn't obviously fit in an existing spec, skip this part — don't make something up.

• please be specific (in the title and issue) about what you want to change:
  “make it better” means different things to different people!

• please link to the spec section you're talking about, or at least the spec

https://drafts.csswg.org/css-flexbox/#flex-flow-property:~:text=5.2.-,Flex%20Line%20Wrapping%3A%20the%20flex%2Dwrap%20property,-Name%3A

such as flex-wrap,
it has a combination ways to write it - flex-flow
But it's not mentioned here

flex-flow mentioned flex-wrap
but flex-wrap no mentioned flex-flow
so Can we add this infomation in reverse?
I think this is a useful message.( such as for MDN)

[Loirooriol]

But note a longhand can have several shorthands, and this is harder to maintain.
Also consider a longhand defined in a CR spec, would you expect it to include a new shorthand defined in a draft? Things get messy easily.