Hi @Bettinahorvath
This is a bit tricky. But don't worry
Try the following way.
In Portal management:
1. Under content > Content snippets
2. Select "Account/Register/PageCopy"
3. Under the value section, paste the following code
<script>
console.log(555,"hiding bluebox");
$("#content-container").hide();
</script>
Note: Replace the id name with the id name you have found. highlighted below for your reference

4. Hit save and close
In Portal studio
1. Press sync config and hit browse the website and press ctrl + F5 together to hide your blue box
Hope it helps.
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