Fixes

• [8.9.1 0b6895a] fix: split screen terminals sometimes incorrect handle exit
  Date: Tue Jun 9 17:47:27 2020 -0400
  2 files changed, 25 insertions(+), 7 deletions(-)

• [8.9.1 900534c] fix(plugins/plugin-client-common): top tab buttons should be owned by the top tab stripe
  Date: Tue Jun 9 16:25:19 2020 -0400
  5 files changed, 128 insertions(+), 67 deletions(-)