The tooltip in the Saved Hotbars disappears in 24w06a

When you open your saved hotbars in 24w06a (saved in a previous version, v.g. 1.20.4), the tooltip in every empty row of the Saved Hotbars has disappeared.

Steps to reproduce:

1. Run version 1.20.4. In Creative Mode save some hotbars with C+n.

2. Run snapshot 24w06a. In Creative Mode open the Saved Toolbars.

Observed result:

You cannot see the tooltip in every empty row.

Expected result:

You should see the tooltip in every empty row, as it was in 1.20.4

Please note that when you run 24w06a without previously saved hotbars then you can see the tooltips.