Flow bugfix releases: 4.3.16, 5.0.15, 5.1.9, 5.2.5 & 5.3.1

Announcements
1

I tagged bugfix releases for Flow. They fix some rather annoying bugs and other issues.

Thanks to those who contributed!

2

Please note that a bug has creeped into these releases via

Technically this should only impact errors during the compile step, but be aware.