Technical

The PARM error is not limited to Illustrator. What Tech has found is that sometimes (for unknown reasons) the CEP DOM will go out of sync and miss-reference elements. Tech found that on some occasions when using code to:

(a) open/close new documents frequently
(b) access many properties of elements

The DOM in some cases will miss-reference element properties. The reason why Illustrator in particular needs to close and re-open is because of the way the CEP JavaScript DOM works with Illustrator specifically.

The Adobe CEP JavaScript DOM

Each DOM in Photoshop, Illustrator and InDesign are very different in its core nature. Although the framework elements are similar, there are key differences in each which causes Illustrator to crash on PARM.

Environment States

Photoshop is non-persistent, and naturally will kill-recreate the DOM on load.

InDesign is sub-persistent, and will create-reload the DOM, unless the Extension is reloaded via the menu to kill-recreate the DOM and re-load.

Illustrator is persistent, and will create-reload the DOM only.

CEP Error Capture

Photoshop and InDesign on error, will stop the execution of the current code and send the error object to the responder.

Illustrator on error, will stop the execution of the current code and throw the error in the DOM.

Why does this Matter?

This is why Illustrator crashes, it is a persistent system and it throws a core error. This causes the DOM to ”crash” and without a kill-recreate, its impossible to re-load the DOM without restarting Illustrator.