I've changed the way libsoup works at the request of the security team. This change will hit GNOME:Factory today, and Factory some time this week, I guess. This does not change 11.1, 11.2 nor 11.3.
A recent change in upstream libsoup made it use only SSL 3.0 for https, because of bugs on various servers, which were causing issues when libsoup was trying to use TLS. However, the security team wanted to keep TLS if possible, so we patch this behavior. Note that upstream wants to fix this correctly in the long term, but it requires rewriting quite some code (while our patch is just a one-line patch).
As a result, libsoup users *might* have issues on some https websites. If this happens, this will be most visible in webkitgtk, and therefore in epiphany. If you hit such an issue, please file a bug and cc me.
For the background story about this, go read https://bugzilla.novell.com/show_bug.cgi?id=634040