Customize text in pop-up confirmation messages on client side booking

When clients book, reschedule, or cancel, an appointment they see a confirmation pop-up message (see images attached). This is nothing to do with the email confirmations set up for each service, this is just a web browser pop-up box that is part of the process of using the client side bookings webpage. Would be great to be able to customize the text in these pop-up messages. If this is already possible please let me know how to do it.

Some examples:

• "Thank you for booking with us!" is inappropriate for me as there is no "us", just me. A shorter "Thank you for booking." would be universally appropriate.
• "We'll send you..." doesn't work when there is no "we", just me. The "You'll get..." is a more versatile option but is not used consistently across the three default confirmation pop-ups.
• This may just be personal preference but a short and sweet "You'll get confirmation by email" is easier to understand and better UX than the default "You will get a confirmation message in email shortly".
• Maybe this is a step too far but wouldn't it be great if the tone of these messages match the business? A casual, chirpy "All done!" will work for some but not others. I'm ashamed that my business is presenting this default text to clients - it clashes with the impression I like to present.