Thanks and glad you found the culprit. This really isn’t a case of the text editor being fragile. There are so many 3rd party plugins out in the wild, it’s impossible to test against all of them. I’ve looked at the plugin you mentioned and it looks like it is only compatible up to version 3.9.2 and it doesn’t appear to be supported any longer from what I can tell. The problem with plugins such as this (not to bash them in any way) is that when they become dated and unsupported they tend to cause all kinds of compatibility issues throwing JS errors which conflict with allowing BB to run as it should.