Can't go under something when too fast as a Platformer Character. (Even if hitbox fits)

Platformer Characters are coded so they can work on all framerates, however when going too fast, and going under something. They end up getting stuck.
Now, this usually doesn’t have to be an issue, but players on lower framerates have this problem when going normal speed whilst sliding.

I’ve ensured the hitboxes are correct AND I just started making this character, meaning it’s not something I’ve done.

TL;DR: If you’re character is going too fast for the current framerate, going under tight gaps is impossible even if the hitbox fits.

https://files.catbox.moe/sr6d90.mp4 (video of the bug in action.)

The character goes out of the camera before it collides the platform. It’s hard to tell what happens.

Have you tried to add 1 pixel in the gap?

His hitbox is at least 15 pixels smaller than that gap.

GDevelop Bug in Action

Sorry about the wait. Here’s a fresh project I made with the player going >1k max speed and attempting to go under something. The current speed is displayed on the top right of the screen along with FPS.

When ever I have less than 1k current speed, the hitbox fits right under as it should, but whenever you’re going too fast, it gets stopped.