On Ubuntu 22.04, I have switched 'temporarily' to transmission-qt.
sudo apt install transmission-qt
Then you can create an alias to temporarily replace the faulty 'transmission-gtk'.
alias transmission='/usr/bin/transmission-qt'
transmission-qt doesn't exhibit the faulty behaviour (and CTRL+S is back).
On Ubuntu 22.04, I have switched 'temporarily' to transmission-qt. '/usr/bin/ transmission- qt'
sudo apt install transmission-qt
Then you can create an alias to temporarily replace the faulty 'transmission-gtk'.
alias transmission=
transmission-qt doesn't exhibit the faulty behaviour (and CTRL+S is back).