Inline mention of another Object

I'm not sure this is a bug or intentional, but when I use the "@" to search for an object an insert it inside my paragraph in the block, it gets insert correctly. However, when I press delete, it doesn't delete the whole inline mention of the object. In other words, it doesn't treat the inline mention object's words as an object, but rather individual words.

I expect to be abl

e to remove the whole object from inline mention in the editor when I press 'delete'.