I recently changed versions of Linux Mint Cinnamon, from 17.3 32-bit, to 19.1 64-bit. I moved my .thunderbird directory from the hard drive my old installation was on, to the new one. My accounts and addons seem to be there, but some things aren't responding properly. Things like the account settings screen, the right side of which stays gray and blank (though the cursor may change to a text-selection cursor, depending on where I hover in the empty gray), no matter what item I click in the left panel, which doesn't highlight. Though the account actions button seems to work, and I was able to add a mail account with some struggle, as the text input box for the account name would not respond until I held down a button on my keyboard until it repeated several times, then I could type in the address. The ok, cancel, and x buttons work, though. Also the Thunderbird preferences screen is similarly uncooperative. Sometimes the top buttons work, but the rest of the dialogs don't work right, similar to the account settings. Like the account settings, the close button and the x do work. Safe mode didn't fix the issue, the windows got similarly stuck. Renaming my prefs.js file to prefs.js.bak wasn't much help, as none of my accounts were showing then. The settings dialogs did become responsive, at least, when I tried that. Where do I go from here?