====== focus writer ======
  * https://gottcode.org/focuswriter/
  * 집중해서 글쓰기만 하는 편집기.
  * 스케줄링 등도 가능함.

===== 설치 =====
  * https://flathub.org/apps/details/org.gottcode.FocusWriter
  * https://launchpad.net/~gottcode/+archive/ubuntu/gcppa