Rich text message display and editor toolbar are controlled by a single option/toggle
I can toggle Rich Text toolbar by clicking "Enable rich text" button (which should have two states: pressed/released — enabled/disabled), but it works for current chat tab only.
I would like to disable it completely for all the chats. I somehow did have that configured, but recently Leechcraft lost all my GUI preferences.
P.S. "About > Authors" still has 2015 as final year:
Georg Rudoy aka 0xd34df00d Lead developer and original author. Years: 2006–2015