The most recent update doesn’t fix anything. I received the following email from Jetpack and the suggested plugin worked for me. I disabled the plugin after the update and the problem returned. Re-enabled the plugin and everything’s fine.
“This is most likely related to https://github.com/Automattic/jetpack/issues/7598
Would you please see if there’s any improvement under the current version of Jetpack if you add in this plugin? https://github.com/georgestephanis/disable-grunion-editor-view/archive/master.zip
To do that, download it, then upload the .zip file via Plugins > Add New > Upload in your site’s Dashboard.
This will disable the new contact form editor which is likely causing the problem. (the old contact form editor will be used instead)
Once the next version of Jetpack is released, it should be safe to disable this temporary fixer plugin.”