I have never seen this issue. When I click the proper choice with a mouse or touchscreen or I use the up/down keys and then hit the Enter key, the proper choice immediately replaces what I typed before into the addressing field.
I have a few questions for you:
- Have you always had this problem, or has it only recently shown up?
- I assume that you are using the web interface at https://www.fastmail.com and not the iOS/Android app. Is this correct?
- What browser are you using? Has it been updated to the latest available version?
- Are you using a PC, Mac, or some other device?
- What operating system are you using?
- How are you selecting the email in the drop-down menu? Are you using a mouse to click it, or using the up/down keys then hitting the Enter key?
My initial guess is that this is due to come browser add-on or extension. I hope you find a solution soon. If we can’t assist you here, you should file a Fastmail support request from the website.
Bill