Hello @bssienes,
I used js under the profile Web Page and it works:

For that i wrote the following code into the Custom Javascript box:

$(document).ready(function(){
var message = $('#ContentContainer_MainContent_MainContent_ContentBottom_ConfirmationMessage > div > div > div')
//console.log(message.text()) not needed
if (message.text() == 'Your profile has been updated successfully.') {
message.text('Test text')
}
}
I used the if-condition in case the message of the selected div is something else as long as the success message is not displayed.