Hello, noobsqoou! Thanks for the suggestion regarding flying mounts, I've tested 4 of them (the witch's broom, fishron, cosmic car and black spot)
They seem to have no impact on the behaviour. In one world they all work, in another one they are all bugged))
For the developers/testers , I'll post the saves here;
In the world called "Bored Afterworld" it is bugged with any mount and wings. It is true for any newly-generated world in my case.
In the world called "Builders Workshop" it is OK
In normal playthroughs its okay too
P.S. the "bored afterworld" was generated in 1.4.0.5
Tested on the following, if needed
1)Windows 10, steam version 1.4.1.2, keyboard/mouse. CPU: lntel core i9-9900k, GPU: Geforce RTX 2080 Ti, 32gb ddr4, screen resolution – 2560*1440
2)Windows 8.1 (also bugs), CPU: AMD A10-4600m, GPU: ATI Radeon HD 7660G + 7670m, 6gb ddr3, steam version 1.4.1.2, keyboard/mouse, screen resolution –1366*768