How to know which component was added in MissingScript?

Unknown

My old project has alerted that there is some component is missing (broken). How to find it’s name to fix?

The only way to do it is to open the scene/prefab file in your text editor and find the uuid of the script where it’s attached. It’s a bit hard to figure out what your looking at, at first, but you should be able to figure it out. Once you have the uuid you can use that to search for it in Assets, just click the search magnifying glass and choose UUID used by, or UUID.

Thanks you. I have solved it by looking in an older git version. But if we dont have git then your approach is solution!