(This issue is unique to the latest recent pre-release, and was not present in pre 1)
The player is no longer able to walk, or more noticably sprint across one block wide gaps since the latest pre-release. This behavior is useful for parkour maps, and has been functional for many versions now alongside being considered intentional behavior based off the resolution of MC-2301. The issue is far more noticable with speed, as when the player has a normal running speed, the behavior can be inconsistent. With speed, the behavior is very consistent.

Steps to Reproduce:

1. Create a string of alternating blocks on the ground:
   (leaving space on one end to start sprinting)
   
2. Get speed:

   /effect give @p speed infinite 1 true
   

3. Start sprinting across the gaps

Observed Behavior:

The behavior immediately falls into the first gap, instead of sprinting over it.

Expected Behavior:

The player would sprint across the gap(s), like in previous versions.

Screenshots/Videos:

1.20.5 Pre-Release 1:
No speed:
1.20.5-Pre-Release-1-No-Speed.mp4

Speed:
1.20.5-Pre-Release-1-Speed.mp4

1.20.5 Pre-Release 2:
Speed:
1.20.5-Pre-Release-2-Speed.mp4

Notes:

1. As stated in the top of the description, while this behavior may not be incredibly consistent, it is useful for certain creators (primarily parkour map creators)
2. Related to MC-2301