Hi,
This is only for information. On my setup with loads of plugins and dropins I had the problem that Visual Composer would not save.
After extended tests I found that WP Editor was the culprit. I really do like the plugin but with Visual Composer it is not need that much.
Obviously because I use so many plugins the reason my be far more complex but I have found my solution.
So I am sorry to say that I have now, after many years of happy use, deleted WP Editor.