Font character textures ignore whitespace after, but not before

The bug

Font characters will ignore any whitespace after the character's texture in the texture file. However, preceding whitespace will still be counted as part of the character.

It is therefore impossible to have a font character with whitespace after it as part of said character.

How to reproduce

1. Download and apply the attached resource pack
2. Type this: |¬|

Expected results

The distance between the central character and outer bars would be identical. Either both gaps would be counted as part of the character, or ignored outright.

Actual results

It is much closer on the right.