I can no longer send an email to myself in Thunderbird; it shows up in the sent box but never arrives.
I can send and receive Thunderbird emails to/from other people, but if I send a copy (or blind copy) to myself it never arrives. If I send a message just to myself, it shows up in the sent box, but never arrives in the inbox. This is a recent problem. It always used to work (summer, 2016), but not in the last week or so.
Wšě wotmołwy (1)
Who is your email provider? Some, notably Gmail, don't send copies to yourself, arguing that you already have a copy in your Sent folder.
Do you have an alternative email address that you could send to? Does that work?