How to fix the cursor change in code playground ?

Question

I have a problem with my cursor, i was coding when he changed..
He was like this before : |
Now he's like this : _
The problem is when i write on a line, it erase all that i haved wrote before on the right..
This appeared only on code playground, i think it's very simple to change but i don't now how i have doing this.. Any idea of what i have messed up ?
Thanks for help

Answer 1

ehm, I think you pressed a button, (I always have the same issue, lol), I don’t know what button, but what I do is pressing all the buttons with small text on it on the right side, ( i have a qwerty) hope it will work

Answer 2

Thank you for reply @jelger.js !

I have find the button, that's Inser, one of the six to the right, above the directonal buttons.. I have a azerty so i don't know if he have the same name but he is just above the delect botton.

That's all ! So simple isn't it ? ^^'