@Looi Tan more generally you might have also hit "f" and typed some text which would have applied a gibberish filter that would hide all cards, if you look in the top right you'll see a little green "0 search results" with a little white "x" you can click on to clear the filter.
Hello Community! My name is Brittany Joiner and I am a Trello enthusiast and Atlassian Community Leader. I'll be sharing with you a series of videos with my top tips on how to best use Trello...
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