As folk use email apps or web email and there are over 100 of these I think you should reply to your own post with a little detail about what app you use.
In my inbox I had an email with a title referring to Insurance.
My usual procedure with this type of spam is to immediately delete them.
This one did not have the usual little square box in the front in which to check and chose a destination for it, it had a dotted circle with a dollar sign in the centre. This made checking it without opening it impossible, as checking the dollar sign opened the advertising page.
I decided, after closing the advertising page, to sort all the other emails in my inbox and try to delete it when I had dealt with the other emails
The last email - now beneath the "offending" one - was dealt with and after checking it's box, I moved it to a chosen folder.
When the move was complete, the inbox was empty. Going to the folder that I had sent the email to, I dicscovered the "offending" email had been transferred with it to the same folder.
I returned to the inbox to make sure it was not there, which it was not, I then reopened the folder to try to deal with this odd email, it was no longer there.
I can not find it in any of the folders that I used today, and it does not show in the Inbox, spam, trash etc.
I am not sure about it's location, and as my anti-virus programme does not search my email folders (Yahoo) I have no way of finding it there.
I am slightly concerned that it may be searching for email addresses to propogate a spam list.
In any future case of a similar email appearing, would someone be kind enough to advise me how to deal with it, and how to delete it before this happens again.
Thank you in advance for any assistance.