[Koha] Need help to reconfigure Koha Mail with Gmail

[Chris Brown]

Dear Koha Community

Our koha mail system is set up to use a gmail account to process outbound
email, using the "less secure apps" option in the gmail account. This has
stopped working for us (and I'm sure for many others) now that Google have
disabled this feature. I am looking for specific advice on how to
reconfigure Koha so it continues to work with gmail (setting up an "app
password" perhaps?). I have seen a little discussion about this on the list
but no real guidance. Can anyone help please?

We are running Koha 19.11.22 (installed from packages) on Debian and we're
using postfix 3.1.15 as our mail transport agent.

Thanks!

Chris Brown (Greenhill Community Library in the UK)