Hi @kivanc sarlar ,
Welcome to the community!
First of all clear cache & data from the app or browser then login to your account! After that try to install the add-in! (Make sure to tale a back up of your browser before clearing the data!)
Please read and follow these article/documentations
Hello Community! My name is Brittany Joiner and I am a Trello enthusiast and Atlassian Community Leader. In this video, I'll share my favorite Trello templates. Templates mentioned in ...
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