Placeholder height too big in Menus page in WordPress

[alexvorn2]

We need to decrease the height of the placeholder.

Maybe the latest jQuery made them bigger who knows.

Please look at the video I uploaded on youtube that shows what is the problem.

​https://www.youtube.com/watch?v=jSnGVJGpqzc

[alexvorn2]

So to fix this we need -2px (to remove 2 pixels) from placeholder.

[welcher]

Intial Patch

[welcher]

@alexvorn2 thanks for reporting! I've attached an initial patch for this.

[peterwilsoncc]

Switching milestone due to the focus on the new editor (Gutenberg) for WordPress 5.0.

[afercia]

After a bit of code archeology, seems to me this happens since the admin redesign in 3.6 :) where the top margin of .menu-item-bar was decreased from 13px to 9px but the top margin of the .sortable-placeholder stayed to 13px. These margins need to have the same value to avoid the "jumpiness" when dragging items. Patch incoming.

[afercia]

Also the sub-items need to have their top margin decreased, it's still margin-top: 13px;.

[afercia]

For clarity, see in the GIF below the bug 41160.2.diff​ addresses: notice the "jumpiness" of the elements below the ones being dragged and their margins changing while dragging.

[afercia]

In 44567:

Menus: Make menu items not jump while dragging items.

Props alexvorn2, welcher, afercia.
Fixes #41160.