Thank you again for your reply
- There is no Display setting, but in View, I have: Layout button sequence: Editor | Viewer | Split view
- I have: Joplin 2.6.10 on Linux kernel 4.12
- I am using the Dark theme
- Editor font size: 15
- Yes I know about the "disconnection" and yes, everything is disconnected and supposed to work in MD mode. If I connect it again I can easily modify the MD with an external editor