v5.8.9

• store last good version in separate debug info file
• fix race condition when server has uid but no header data yet
• fix running external commands under termux
• add make.sh support for termux
• add support for custom browser
• log last good version if different from current
• improved handling of folder uid invalidation
• add support for showing folder message count in top bar
• fixes #182 - add support for multiple instances