So....today I get a call from my neighbour complaining that her emails had changed
it's only round the corner, sure enough every email opens in draft!!
How it happened I have no idea but I found an extension which you can set the default flags for folders, Hers had the Inbox set as both Inbox and Draft ticked!
Unticked Draft, problem solved... till next time
She has been using Lubuntu for about 10yrs now on version 22.04+Thunderbird collecting from Gmail.