One can un-check "close window on delete", and carefully,
Go to tools/options/advanced/config editor. The item copied below is
#1262 (at least on my system), of more than 1800 settings.
mail.tabs.closeWindowWithLastTab;true
(change to "false"
Save setting by entering on OK.
Never change more than one setting at a time in config editor unless you
are _very sure of what you're doing.
This should work for you.
B.H.
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Bando?ers
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>This should work for you.
Indeed it did! Many thanks - that problem had been bugging me ever
since I've been using Thunderbird.