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NEW : We have got a new blog where we post some interesting SWF internals info.List of issues
#1723 Undo for P-code
> What steps will reproduce the problem? Edit P-Code. Save. Do not change active trait. Used to be able to click edit and ctrl+Z to undo changes still. Does not work anymore. > What is the expected output? What do you see instead? Used to be able to click edit and ctrl+Z to undo changes still. Does not work anymore. > What version of the product are you using? Is it "nightly build"? Which operating system do you have? v14.4.0 > Please provide any additional information below. If the problem is related to a SWF file, attach it here, otherwise we can't help you.
I think that was an unwanted feature. Anyway, we should still implement some kind of undo for scripts...
Title: Undo no longer works after saving P-Code→Undo for P-code
As an update to this: Sometimes the undo does still work. Sometimes it doesn't. I've tried to figure out what the deciding factor is but so far haven't been able to narrow it down. Definitely would be handy to have because sometimes after editing the pcode you'll see the resulting AS is not what you intended, so being able to quickly click edit and undo it is very helpful.