System Information
Operating system: Windows 10
Graphics card: Intel HD 620

Blender Version
2.80, since forever.

Short description of error
Like title says, I want to connect 2 vertices so as to split the face they share.
But the resulting edge seems weird like it's hanging or something and when I select a half of the face the whole previous face is selected as if the edge is not there.
See attached pic.

Exact steps for others to reproduce the error
Create a new Cube.
Select 2 coplanar vertices.
Hit F to create a new edge between them.
Switch to Face Mode and select newly made faces.

EDIT:

This appears to be normal behaviour since it's present in older stable versions.
But this could call for a new feature in Blender to split a face between two coplanar vertices instead of float right there.