Emails I know nothing about appear in my inbox for a few second and the vanish but do not go to spam or deleted.
This is not an idea but a request for information from Yahoo as to why?
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Hi there! Sometimes when a mailbox behaves like this it’s because of another program or app the account is being accessed from. Syncing issues between the account and a mail app can cause emails to be moved around oddly.
If you access the account through a mobile device or app, you may want to remove the account from the device and re-add it to resolve any syncing issues in the future.
Hope this helps!
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Jon Shortt commented
If it was possible for your feedback section to be less of a popularity contest and more direct improvement tool, that would be good.