Mailtrack (recently rebranded as Mailsuite) is one of the most popular email tracking tools, though its relationship with Yahoo Mail remains indirect. Currently, Mailtrack does not have a native browser extension for Yahoo Mail. It is built specifically for Gmail and Google Workspace.
How to do it:
If you prefer not to use Gmail, several alternative tracking tools integrate directly with Yahoo or work via IMAP/SMTP.
Why this solves "UPD": eM Client updates independently of Yahoo. Even if Yahoo changes its web interface daily, the IMAP protocol remains stable. You will never need a "patch."
If your Yahoo account is added to the Gmail app, the add-on can track messages sent from that device. Direct Yahoo Tracking Alternatives