[Bug?] On Document Open scripts don't work if the PDF is digitally signed

This is just a random thought, not tested, but I believe running JavaScript is "form filling". Therefore if you lock a file (by signing or security) and don't allow form filling, I'd not be surprised to find that the JavaScripts were dead.

By the way, to remove a post or attachment, click Report and explain what you need to the moderator who will eventually read it.

I've been digging to isolate the problem. But I haven't been able to make a simple form that displays the issue. I'm worried I'll have to post the actual form I'm working on, which will impact my privacy 😞

The specific error I get is: 

InvalidGetError: Get not possible, invalid or unknown.
Doc.external:3:Document-Level:zDocOpen

While the code for that script is: (I included XML Tags for reference)

//<Document-Level>
//<ACRO_source>zDocOpen</ACRO_source>
//<ACRO_script>
/*********** belongs to: Document-Level:zDocOpen ***********/
//If the form is opened in a non-Adobe product, it'll be readonly and pop up an error.
function DocOpen(){
if(this.external){
	app.alert({
		cMsg: "This form does not work in your chosen PDF viewer. Please use Adobe Reader or Adobe Acrobat.",
		nIcon: 0,
		nType: 0,
		cTitle: "Bad PDF Viewer"});
} else { //Unlock the Status field and process
		this.delay = true;

		actionSetVis("Show");

		getField("Status").readonly = false;
		switchStatus();
		if(getField("Admin.Customize") == null && getField("Admin.Save") != null){this.removeField("Admin.Save");}
		this.delay = false;
		this.dirty = false; //prevents Adobe from asking to save the form again.
	};
};


//Required by law. Runs on open every time because there's no conditional.
//Moved from "SORN" to zDocOpen to place it after all other scripts are defined.
app.alert({
	cMsg: "AUTHORITY FOR MAINTENANCE OF THE SYSTEM:\n\
10 U.S.C. 8013, Secretary of the Air Force and E.O. 9397 (SSN).\n\
\n\
PURPOSE(S):\n\
Used to locate or identify personnel assigned/attached to, tenanted on, or on temporary duty at the specific installation, office, base, unit, function, and/or organization in response to specific inquiries from authorized users for the conduct of business. Portions of the system are used for directory service and forwarding individual personal mail received by Air Force postal activities, and for assignment of individual mailboxes. Files may be used locally to support official and unofficial programs that require minimal locator information, membership or user listings.\n\
\n\
ROUTINE USES OF RECORDS MAINTAINED IN THE SYSTEM, INCLUDING CATEGORIES OF USERS AND THE PURPOSES OF SUCH USES:\n\
In addition to those disclosures generally permitted under 5 U.S.C. 552a(b) of the Privacy Act, these records or information contained therein may specifically be disclosed outside the DoD as a routine use pursuant to 5 U.S.C. 552a(b)(3) as follows:\n\
\n\
The DoD 'Blanket Routine Uses' published at the beginning of the Air Force's compilation of systems of records notices apply to this system.\n\
\n\
DISCLOSUE: Voluntary. Failure to supply this information may result in fewer services being available and you will not be able to recieve electronic notifications of recieved mail.\n\
\n\
Submission of this form qualifies as consent for your information to be used as necessary.",
	nIcon: 3,
	nType: 0,
	cTitle: "Privacy Act Statement"});

//Runs SigExtract on open, in case the SigExtract didn't save when first signed
if(getField("Mbr.Sign").signatureInfo().status > 0 && getField("Mbr.Name.Last").value == "Auto filled when signed"){
	Sign();
};
DocOpen();
//</ACRO_script>
//</Document-Level>

I actually work in two versions. And I have the issue in both versions.

Work:

Acrobat DC Pro: 2022.001.20085

Windows 10, Version 1909, Build 18363.2158

Home:

Acrobat 2017 Pro: 2017.012.30205

Windows 10, Version 21H2, Build 19044.1620