Building a Trell Power Up

I am trying to follow the Atlassian tutorial to build a power up found here:

I follow the step to create the power up in the admin console and I see that my power up is enabled. When I try to add the power up to a card I can see the power up, but there is no add button. I’m not sure what I’m doing wrong and hoping someone can point me in the right direction.

You need to add way more information for any to have any chance to help you. We need code, scenario, setup and so.


I have same issue while strictly following the “3-part tutorial written by Bentley Cook”.
The Power Up won’t load in my board at step 3

Here is the code I remixed on glitch : Short Navy Origami
I added a new Power Up in my trello- power-ups -admin page :

  • URL : same glitch URL
  • API Key generated & trello + glitch as authorised origins
  • card-buttons capacity activated

On my Trello board, I saw and activated my Power Up in Menu-PowerUp-Custom

Then, I load the board and open a card to test the “estimate” card button.
I see an empty button for 30s then it disappears.
On dev console, I have lots of warning and errors, last of them being:

  • IndexedDB timed out. [instrument.js:111:32](trello-client node_modules @sentry utils esm instrument.js)
  • Error, timeout while initializing index iframe for glitch ~short-navy-origami. Timeout=30000ms [instrument.js:111:32]

I tried lot of different configurations : different browser, different network, different computer.
I tried cleaning cookies and browser, authorised all cookies by default, deactivating all browser plugin and extension
… all the same

Any idea ?

Tutorial available here :

Hello, seems that the used PowerUp URL was wrong.
Now using and everything’s fine

Not sure what development environment you are using, but I created a Tutorial for setting up VS Code (including best extensions) and creating a Trello Power-Up (using pure ES6), with details and step by step explanation of the parts. This is specifically done so that you can live-edit / debug / update with a local Node web server.