I recently purchased a new PC, with Windows 10. I installed Thunderbird, and it works fine. However, the mouse over function is not working - I need to click into the different sections of the pane/window to scroll etc. For example, when using the classic view, with the 3 panes of: message list, message body and folders, if I am in the message list pane, click on a message in that pane, then move my mouse to the message, I need to actually click in the message to be able to scroll or navigate within that pane. I have used Thunderbird on numerous other computers, both PC and Mac, and this has never been the case - I could always mouse over to the other pane.

As well the scrolling speed in Thunderbird is completely different from other programs on the PC. It is very fast - impossibly so - but the speed is fine in other programs (MS Office, web).