Why Does Card Mirroring Require Full Access to the Original Board?

[Nils Geylen]

A mirror card is only visible to users who have access to the mirrored source.
I can come up with a lot of reasons why that is. 

Members should obviously not be sharing board contents not everyone is allowed to see.

Okay, but imagine another use case...

Say I have a product board, a store location board, and a PR board.
They're all for internal use in their entirety, but now I want to share a catalogue of cards to some of my customers.

I mirror a few samples from each source to my new target board and add a couple people as observers.

They have no access to the mirrored sources, so they get this:

They see the mirror card placeholders but not the contents, and all they can do is request 'access to the card'.

However, on my end, that translates as 'so-and-so wants to join your board'...
Which is indeed a no go--I'm not gonna allow outside observers to all my source boards!

So unless there's a technical reason, why shouldn't I be able to:

• share a board with mirror cards with observers
• have them see the mirror card, and its contents
• have them get the message "You are viewing this [mirror] card outside of its original [mirrored] location"
• have them not get the option "For more actions, go to the card’s original location"

That would be a Mirror & Show approach I was hoping to get.
Or at least some board option to "Allow observers to see mirror cards"... 

Mirroring solved a lot of troubles with copying cards, and then having to go edit and update every possible duplicate if the original changed.

But I was a bit disappointed when I saw this limitation.

So does this have a technical reason, or is it a programmed decision?

Seems like just another instance where Trello assumes everyone is tightly grouped within a team but apparently never shares stuff outside.

[Caity · Accepted solution]

Hi @Nils Geylen! Thanks for giving Mirror cards a try and sharing this feedback with us. I know many people were hoping to use Mirror cards this way, and I can definitely understand why you'd be disappointed by this.

You asked if there was a technical reason. Mirror cards are not a separate card that syncs with the original; they're a reference to that card, almost as if you embedded the original card in another board. The data from the original card isn't actually stored on the Mirror card, so, in order to view that information, you need to have permission to view the original card. Right now, however, there's no way to set permissions for an individual card; the permissions are always inherited from the board. In order to allow Mirror cards to be seen by users without access to the original board, we would need to first have a way to set distinct card permissions, which would need to be its own project.

I wouldn't rule out the possibility of ever having card-level permissions in Trello; however, it's not something that I would expect in the near future. For now, we recommend the Unito Power-Up for situations where you need to sync card content across boards with different access levels.

[Nils Geylen]

Thank you for your clear on-point response!

I'm good with this. Totally understand this isn't something you flick a switch on within the system and it's solved.

Native mirroring was a longstanding want for many, including myself, and even today I realized it helps me out in even more ways I had thought of. I'm still stoked with how good this feature has turned out! 

[In Style Patios and Decks]

Hi, 

Is there any other solutions other than the Unito Mirror powerup?
At $299 per month for 100 mirrors it is quite excessive!

Does Jira allow permissions at a card level?

Thanks