Several of our users are experiencing an issue when they are composing an email in Lightning.  Many times as they are typing, the email cursor either stops or goes elsewhere.  I have not experienced this myself, but I have witnessed it.  

I saw this was a known issue in Summer '18 and was fixed, however I see an idea out there from users stating this is still an issue.  Does anyone know of any official statement from Salesforce on this?  I need to tell our users why this is happening.