Ender Dragon does not come to the end portal

1.14 pre2. 
Generaly not updating states?
Stuck in "random flying around mode", then after a while also not picking a new location and flying in small circle-eights after having previously flown around, both for an extended period of time of about 3/4 of bossbar of booping with bow pointed on one point in sky, untill killed. Reloging will fix the dragon but it may becomed bugged again after some time.

Bug confimed in 1.14 Pre-Release 2

(Relates to MC-148179)

Still in 1.14 pre-3, 1.14 pre-4 and 1.14 pre-5

Still in 1.14 Release

Forward-resolving to MC-148179, that ticket has a better and more extensive description