You want to sell all shares at once without entering the decimal places?
Then install at least the app update 2.43.1 and the option is automatically available.
To use the button, you can proceed as follows:
Click or tap "+Import" and choose the portfolio you want to add the transaction to.
Select "Sell" for the type of transaction.
Now select the security or the position.
In the next step you can simply click on "Sell all".
Finally, just tap "Add transaction".