Custom editor reopened from untitled does not properly wire in dirty state?

[bpasero]

Steps to Reproduce:

1. open an untitled text editor and type some content
2. reopen with hex editor

=> the editor indicates dirty, but e.g. the explorer does not

From my testing it seems like in this case the working copy that is created does not emit a onDidChangeDirty event?

[bpasero]

I see the dirty indicator but it now accounts for 2:

I think the untitled editor model is still around?