Share button autocomplete can get in a state where it will not share with a particular email

To reproduce:
find a page to share
click the share button
paste an email into the autocomplete field and press space before the autocomplete has a chance to suggest any values
delete the space, auto complete will not suggest a value to add
retype the email into the share box, auto complete will not suggest a value to add

This is not limited to pasting an email, can reproduce this by typing an email if you pause after typing the full email and then press a space.

I can reproduce this on EAC, may need to slow the process down if running locally.

To work around this, refresh the page that you want to share, and do not put any whitespace after the email address in the autocomplete field.