Puppet ENC missing from UI

In the ‘new UI’ there was previously a very useful “ENC Preview” on the “Puppet” tab. But after upgrading to 3.9 it’s gone.

Expected outcome:
View the Puppet ENC yaml in the web UI without resorting to the legacy UI.

Foreman and Proxy versions:
All 3.9.1.

Foreman and Proxy plugin versions:
bootdisk: 21.2.1
puppet: 6.1.1
setup: 8.0.1

Distribution and version:
Ubuntu 20.04

This has recently been brought up here: YAML Button in Modern UI - #5 by Alexandre_Barth
That thread also already contains proposed fixes (I have not checked the PRs themselfs) but you might want to check there and maybe chime in on the discussion or try out the proposed patch until a fix is oficially released.