My instance of Thunderbird was recently updated to v78.5.0. With this update, I no longer am able to expand recipients of existing emails. For example, note the following: * * I receive an email. * * I wish to reply to the sender, and add additional recipients. Previously, I could highlight the recipient field, and additional recipient fields would open allowing me to enter additional recipients to add to the reply as .cc or .bcc. This ability to expand a recipient list is now gone. This functionality needs to be restored, or a clear way to restore the previous version of Thunderbird provided. It is unsatisfactory to have prior functionality removed that your end user community has been using for years. Please advise at your earliest convenience.