Aww you make me feel bad now mate, but really, thanks for your kind post buddy!
I'll post if finding something, but unfortunetly don't hold your breath, because I cannot really troubleshoot this in blind, and tried lookup if I couldn't install synology DSM 7 in a VM and test there, but not possible, well a workaround exist but you need have a NAS firstly, and export it to VM, or something alike.
Anyway, I had a thought about making a deluge plugin that supplied that certificate file and defined the needed env-var to that file(so didn't need know your certificate file location specifically), and also actually did make that yesterday, but problem is it's loaded to late to take effect, so not a fix. I'm thinking maybe to restart the libtorrent session(or core deluge session maybe, dunno) additionally afterwards, though have never did that before honestly, only ever added/changed some params to current lt session at most, but probably is becoming little to advanced for me propperly now unfortunetly, but as said, if succede then will post back of-course.
Btw, after making that plugin I also saw in the deluge-code that certifi's where() function used for windows probably infact is the reason works in windows, as specifically sets that env-var(SSL_CERT_FILE) which I didn't remembered before, as only wen't from memory there - that is loaded from deluge.common, so early enough to work seemingly, in contrary to a plugin.
Hopefully others have ideas of-course too.
Edit: Sorry didn't work by restarting libtorrent/deluge session from my plugin sadly, and I now also realize I completely forgot unexported env-vars aren't propogated out and only inherented by childs, or something of that sorts, so this would'nt work anyways regardless. Then seemingly you possibly can do something from pyopenssl, but problem is that libtorrent don't use that for https announces, but again will post back if finding something, but now i'm pretty much certain this will go nowhere, sorry couldn't help.
Edit2: Sorry still nothing, but just quick last note about you guys(synology DSM users) could also instead install deluge manually in docker, which doesn't have this issue, guide here:
https://mariushosting.com/how-to-instal ... ology-nas/. I think you need add extra line of '-p 58846:58846 \' to the docker install script on said guide, if wanting use GTK-UI to connect to it(thinclient) and not only webU. If wanting stick to regular synology package, then as said can use ltconfig plugin to workaround it, if accepting the security risk.
Deluge
