Looks like I might have found the root cause of the problem, and it's bad news because it looks like it will eventually affect Chrome as well, not just Canary.
As of right now, Chrome main is on Chrome build 64, and Canary is on Chrome build 66. According to this news post and the official thawte post below, a lot of certificates will be distrusted by Chrome starting from build 66.
https://www.itnews.com.au/news/chrome-t ... ear-469688
https://search.thawte.com/support/ssl-d ... id=SO29613
I checked the hosting servers behind mangafox/fanfox and it looks like they're using thawte certs that fall under the category that will be distrusted, so this is probably the reason it's not working for Canary, but working for Chrome currently.
Guess it's a server side issue that they have to update their certs quickly to satisfy new industry standards.
Question now is - are we confident that those hosting services (the one I saw hosting one of the fanfox manga i randomly picked was secure.footprint.net) would update their certificates before Chrome hits version 66. If not, we need to migrate off mangafox/fanfox quickly so we need some serious help coding for a new site mirror
I'm guessing the same problem applies to mangahere as well