If an Element terminates with an inline DecortorNode (here using Equation) then deleting the new line below the decorator also deletes the decorator.

Lexical version: v0.21.0+dev.esm

Steps To Reproduce

1. On line 1, insert an equation - make sure there are no text nodes after it.
2. Press backspace from selection offset 0 on the line below.
3. The DecoratorNode will be deleted.