Thanks for contributing to our forum. There is currently an issue with the newer editor which is causing behavior like you have described to occur when using the Google Chrome browser so, assuming your are using Chrome when this happens, I believe you must be encountering that issue.
As you mentioned, this issue did pop up once before and had been resolved, but it later resurfaced and our technical team is currently working to address the issue once more.
It currently looks like we may be able to get another fix for the issue in place as part of our next release so, although I cannot offer a specific estimate of when the issue will be resolved at this time, I do not expect it to take too long.
We apologize for any inconveniences this issue may be causing.