It looks like the problem was a social media blocking extension on Adguard I use with Safari combined with weird cache issues on the iPad.
Thank you for checking on my site and helping me!
I am running Safari 13.1.2 on Mac OS 10.15.6. Also seeing the same behavior on iPadOS 13.6.1. Just upgraded to WordPress 5.5, Twenty Twenty theme version 1.5. Everything does work on Safari on iPhone.
Regular widgets like Archives and categories work just fine. Jetpack widgets Subscribe to blog via Emil and RSS link do not work in Safari desktop although I have found that Blog Stats does.
Ah, that explains it, thank you.
I have narrowed down the Jetpack issue as well. It turns out that the Jetpack widgets are not showing up on desktop safari, they render fine on both Firefox and Edge.I’m still not sure if it is a Twenty Twenty issue or a Jetpack one because the regular widgets show up on my iPad and desktop Safari.
