The item durability bar visually adds a "slice" of durability when the item is held on the cursor.

Steps to reproduce

1. /give @s diamond_sword 1 1
2. Look at the durability bar
3. Click the diamond sword

Observed results

Expected results

The durability bar displays exactly the same.

Notes

This was once blocked by MCPE-105893. If I recall correctly, before that issue, the colour would also change to reflect the visually higher durability. This (colour change) seems to no longer be the case after MCPE-105893 was fixed.