Thunderbird 38.6, new installation on Windows 7 Home Premium. Set up POP3 mail accounts. On start-up, program hangs and hangs. Eventually get some message about a script not working or not closing. References "chrome://messenger/content/folderPane.js:1328" Eventually the program goes forward. Some days, it's two minutes, others it's as long as 10 minutes before any e-Mails download. Error message about script only shows up after five minutes or so, so not every time.