Hm, yeah, that's strange. Your code looks normal, so I'm not sure what it could be.
I just found that there's a v3.01. Want to try that and see if it works any better?
/*************************************************************************************************************
* Adobe Consulting Plugin: getPercentPageViewed v3.01
*
* Requires AppMeasurement, the handlePPVevents helper function, and the p_fo plugin (included in the BEGIN CODE TO DEPLOY section)
*
* Release Date: 2018-08-13
*
* Arguments to Pass In:
* pid (optional, string) - a variable that you want to tie the percentage of page viewed to. This would usually be some sort of page identifier. Defaults to the Analytics pageName OR the current URL if not set.
* ch (optional, boolean) - set this equal to false if you don't want the plugin to take into consideration any changes made to the page size after its initial load. true is the recommended/default value for this Argument
*
* Returns:
* Nothing, but will set the following variables in the AppMeasurement object as a new page loads:
* s._ppvPreviousPage = The name of the previous page viewed (As final measurements aren't available until a NEW page loads)
* s._ppvHighestPercentViewed = The highest percent of the previous page that the visitor viewed (height-wise); in other words, what was the furthest point that the visitor scrolled down on the page
* s._ppvInitialPercentViewed = The percent of the previous page that was visible when the previous page *first* loaded
* s._ppvHighestPixelsSeen = The highest number of total pixels seen (height-wise) as the visitor scrolled down in the previous page
*
* Sample Calls:
* s.getPercentPageViewed()
*
* if(s.pageName) s.getPercentPageViewed();
* if(s._ppvPreviousPage)
* {
* s.prop1 = s._ppvPreviousPage;
* s.prop2 = 'highestPercentViewed = ' + s._ppvHighestPercentViewed + ' | initialPercentViewed=' + s._ppvInitialPercentViewed;
* }
*
*************************************************************************************************************/
/******************************************* BEGIN CODE TO DEPLOY *******************************************/
/* Adobe Consulting Plugin: getPercentPageViewed v3.01 w/handlePPVevents helper function (Requires AppMeasurement and the p_fo plugin) */
s.getPercentPageViewed=function(pid,ch){var s=this,a=s.c_r("s_ppv");a=-1<a.indexOf(",")?a.split(","):[];a[0]=s.unescape(a[0]);pid=pid?pid:s.pageName?s.pageName:document.location.href;s.ppvChange=ch?ch:!0;if("undefined"===typeof s.linkType||"o"!==s.linkType)s.ppvID&&s.ppvID===pid||(s.ppvID=pid,s.c_w("s_ppv",""),s.handlePPVevents()),s.p_fo("s_gppvLoad")&&window.addEventListener&&(window.addEventListener("load",s.handlePPVevents,!1),window.addEventListener("click",s.handlePPVevents,
!1),window.addEventListener("scroll",s.handlePPVevents,!1),window.addEventListener("resize",s.handlePPVevents,!1)),s._ppvPreviousPage=a[0]?a[0]:"",s._ppvHighestPercentViewed=a[1]?a[1]:"",s._ppvInitialPercentViewed=a[2]?a[2]:"",s._ppvHighestPixelsSeen=a[3]?a[3]:""};
/* Adobe Consulting Plugin: handlePPVevents helper function (for getPercentPageViewed v3.01 Plugin) */
s.handlePPVevents=function(){if("undefined"===typeof s_c_il){for(var c=0,d=s_c_il.length;c<d;c++)if(s_c_il[c]&&s_c_il[c].getPercentPageViewed){var a=s_c_il[c];break}if(a&&a.ppvID){var f=Math.max(Math.max(document.body.scrollHeight,document.documentElement.scrollHeight),Math.max(document.body.offsetHeight,document.documentElement.offsetHeight),Math.max(document.body.clientHeight,document.documentElement.clientHeight));c=(window.pageYOffset||window.document.documentElement.scrollTop||window.document.body.scrollTop)+
(window.innerHeight||document.documentElement.clientHeight||document.body.clientHeight);d=Math.min(Math.round(c/f*100),100);var e="";!a.c_r("s_tp")||a.unescape(a.c_r("s_ppv").split(",")[0])!==a.ppvID||1==a.ppvChange&&a.c_r("s_tp")&&f!=a.c_r("s_tp")?(a.c_w("s_tp",f),a.c_w("s_ppv","")):e=a.c_r("s_ppv");var b=e&&-1<e.indexOf(",")?e.split(",",4):[];f=0<b.length?b[0]:escape(a.ppvID);var g=1<b.length?parseInt(b[1]):d,h=2<b.length?parseInt(b[2]):d;b=3<b.length?parseInt(b[3]):c;0<d&&(e=f+","+(d>g?d:g)+","+
h+","+(c>b?c:b));a.c_w("s_ppv",e)}}};
/* Adobe Consulting Plugin: p_fo (pageFirstOnly) v2.0 (Requires AppMeasurement) */
s.p_fo=function(on){var s=this;s.__fo||(s.__fo={});if(s.__fo[on])return!1;s.__fo[on]={};return!0};
/******************************************** END CODE TO DEPLOY ********************************************/
