**Steps to reproduce:**
1. Compose new e-mail
2. Click on the slider next to "Return receipt" or "Delivery status notification"
**Actual results:**
Slider moves to the right and turns blue, but no clear feedback is displayed if the action had the intended effect (participants asked me if the action was conducted successfully)
{F2519839}
**Expected result:**
In addition to the moving and changing colour of the slider, there should be displayed a clear feedback that the action was conducted successfully: "Return receipt/Delivery status notification requested successfully." This feedback should be displayed right after the clicking on the slider.