We have updated a number of thunderbird email reader extensions to TB 68.
Addons:
File: gmailui-1.4.2-tb.xpi version:1.4.2 name:Expression Search / Google Mail UI description:Type 'from:fred to:tom' to see all messages from Fred to Tom in the current view. author:Opera Wang V68 by Rich Roth - http://www.tnrglobal.com/2020/05/thunderbird-addons/ homepage_url:https://github.com/wangvisual/expression-search
File: quicktagfilter-1.0.1@tnrglobal.com.xpi version:1.0.1 name:Quick Add description:Quickly add to tag filter author:Rich Roth/TNR Global homepage_url:http://www.tnrglobal.com/2020/05/thunderbird-addons/