There is a problem with global gradient swatches, described at https://illustrator.uservoice.com/forums/908050/suggestions/44461230

Illustrator applies changes to all copies of a gradient in a document when this gradient is changed via a script. It makes sense from a practical point of view, but is devastating for scripts in general.

We can’t duplicate gradients with a script properly, like we can do with any other swatch, because when it's done, the gradient swatch get forcibly added to Swatches and then corrupt the art which uses them when deleted... and it does not break this global link anyway.

At the moment we copy a gradient into the swatch, it will be associated with the first object. If we repaint the swatch to use it for another object, the first object will change its fill momentarily. Just like the video from the issue above shows — https://illustrator.uservoice.com/assets/235626175/linked-gradients-bug.mp4

So we 'instance' gradients instead of 'duplicating' them.
Creating a new gradient via script also creates a new swatch. Deleting either the new gradient or the new swatch also deletes the other. If the need is to get rid of the swatch but not the gradient, that doesn’t look to be possible via with the current APIs. Perhaps we need a new API to delete just the swatch and not the associated global (gradient, pattern etc.).

Having this will allow us to keep gradient changes on one object from affecting other objects. To duplicate, a new gradient will be created and a copy of all gradient properties (type, number of stops, stops) will be performed, via existing app.activeDocument.gradients.add()
Then we will be able to delete the swatch with a new API without crashing Illustrator.

Please, pretty pleas with sugar on top add SaveAsCopy function to illustrator script. All i need to be happy is to bind a script that allows me to save a copy of specific AI art board(s) as PDF with presets. it is impossible to save copy of document without closing current AI file.
I work in print and that is the thing illustrator lack for me, one script command... saveCopyAs.
Why does it matters? because i have tons of print layouts with ton of PDF's to link on aforementioned plates, and i need to sometime go for 3 different export as pdf to get to last print layout... i save a lot of PDFs. Not to even mention small size pdf's that i need to send to clients. There are days that i make the same PDF 7 times before i end with client, and then i do like 2-3 more to have flexo print layout. And after that i have 8 more projects to do. Don't even get mi started on moving something 2mm left and going once after 9 projects and 9 layouts...
So when i have the change done, I want to be able hit saveAsCopy keybind script, then illustrator will nicely ask me if i want to update linked file on layout, i say yes, hit another saveascopy and he will ask me if i want to make an update on final layout for anilox roller, I say yes, hit save as copy, and I AM DONE. Now 9 more.
All that this will give mi is Save of time from saving all this files manually by clicking file->Save as Copy. And that is all i really want, the save in time on repeatable tedious action

I'm not a developer, just an ardent fan of the work that the guys at AstuteGraphics do to improve the functionality of Illustrator.

One of their products they introduced before Illustrator had recovery capabilities was a plugin called Autosaviour. It's a tool that can not only regularly save your files at a given interval but also create backup copies of them too.

I recently asked the team if it was possible to adjust the way backups get created by utilising the 'Save a copy' function so that the original file could remain intact whilst in the background periodic backups could be created. I was disappointed to find that it is not possible for them to do this.

Please make it possible for developers to call the save a copy function within their plugins and scripts.

I checked with macOS X Mojave, Illustrator24.3, and Yosemite, Illustrator CS6.

Below is a sculpt to create a new document, create a rectangle, select and copy, paste and cut. Try it first.

var doc = app.documents.add ();
var rect = doc.pathItems.rectangle (0, 0, 50, 50);
app.copy ();
app.paste ();
app.cut ();

After execution, the user can undo it.
The final process is "cut", but what appears in the menu is "undo paste".
Let's cancel it again. The second thing that appears is "undo cut".
Because of this, when you try to return to the pre-execution state, Illustrator almost always thinks a bit and ends with an error.

The development of ExtendScriptToolKit seems to be over, but we still need to continue using ExtendScript, so this bug cannot be overlooked.

This is a sincere request, so please fix it.

<in Japanese>

私はmacOSX Mojave, Illustrator24.3, そしてYosemite, IllustratorCS6で確認しました。

以下は、新規ドキュメントを作成、長方形を作成、選択してコピー、ペースト、カットするスクプリトです。まず実行してみてください。

var doc = app.documents.add();
var rect = doc.pathItems.rectangle(0, 0, 50, 50);
app.copy();
app.paste();
app.cut();

実行後、ユーザーは取り消しが可能です。
最後の処理は「カット」ですが、メニューに現れるのは「ペーストを取り消し」です。
もう一度取り消ししてみましょう。2番目に現れるのが「カットを取り消し」です。
これが原因で，実行前の状態まで戻そうとすると、ほとんどの場合Illusratorはすこし考え込み、そしてエラー終了します。

ExtendScriptToolKitの開発は終了してしまったようですが、それでも我々はExtendScriptを使い続ける必要があるので、この不具合は見過ごすわけにはいきません。

心からのお願いですから直していただきましょう。