Unions causing climbing/collisions issue in-game

[JJGeography]

Hi all, a few hours ago I got reports of players not being able to climb up stairs (like there’s an invisible block). This has never happened before and I hadn’t changed anything. Sure enough, in-game I’m unable to climb up stairs. However it works absolutely fine in studio. I’m sure something has been changed in the last 12/24 hours for this to happen!

In-game:
https://gyazo.com/ea2617e90ee3d6e1f0d2def714d44f41

In studio:
https://gyazo.com/95934741942e2ff236b893d306c9585d

• This seems to be happening all the time on any stairs in my game.

• Game Dev Life 🎮[Beta] - Roblox

• As I said, this started happening in the last 12-24 hours or so!

Thanks!

EDIT: Discovered some more information.

I deleted this Union here and it now works fine:

It seems as if a new roblox release increased the hitbox size of unions or something as the hitbox was esentially like this:

Union settings:

[Veldaren]

Aside from the bug, a good practice would be to place some wedge (in your case a tilted brick would make more sense), and disable collisions on the stairs themselves.
That way the character doesn’t have to analyze how stairs’ steps work, and instead it’s just climbing a smooth surface. It’s very useful if you want to avoid any difficulties similar to what you’ve shown in the OP.

[JJGeography]

Yeah, thank you! In terms of the bug it seems something to do with union hitboxes/collision detection has been broken!

[Veldaren]

You could try checking how the collision mesh looks by enabling ShowDecompositionGeometry property in settings (you can also use this plugin)

[JJGeography]

Well that’s the thing; it looks fine but in-game the collision hitbox is clearly not that!