BeTheme – broken – js error

Fresh install, no other plugins active. Latest stable Chrome browser. BeTheme premium theme v12.9

1 Created page – Home
2 Set to front page in Settings
3 Added paragraph to content of Home page and saved

On front end I see the paragraph and a blue edit button below it. Clicking Edit changes to 2 buttons, Update and Cancel but title and content is not editable.

js console error: Uncaught TypeError: Cannot read property ‘attachCustomEvent’ of undefined – medium-editor.min.js?ver=ac7e602…:3

Switching to TwentyFifteen works fine. Just FYI as this is a pretty popular theme.

https://ww.wp.xz.cn/plugins/frontpress/