Can't really understand what happens.
I've built https://www.tinkercad.com/things/cbxeExOb0Vv-arduino (kind of blink using only the internal led ... nothing tremendous) by entering the code in text mode (not through the block editor).
Is there any way of knowing what may be the trouble ? Or might it only have something to do with my internet connexion ? Or ... ? Thanks for any help.