Bob posted a comment on ticket #26

Yes, they deprecated 1.0 and 1.1 "no later than December 31, 2023" in their words. I rely on this plugin, and I hope it gets updated, but I see there has been no update in years.. As a workaround, install the "KeeAnywhere" plugin, and KeePassSync will start working again! It must have 1.2 support, and somehow KeePassSyync piggy backs off it.