Sorry, i don't understood.
I see nothing which is "insert before / insert after".


Rather i see an "break at comma" reformating.


I would do it like this:
- format the first lines yourself till the "modified:"

- next do an search&replace:
Find: ,
Replace with: ,\n
[X]Use Escape Sequence

- next do the indenting



@Yutaka, this search&replace doesn't respect this setting:
"Configuration - General tab - Tab/Indent > [X]Enable Auto Indent"
I had expected it would be auto -indent with s&r \n too.