TypeError: _e[_d[i].slot] is undefined when loading the work items in web.

After upgrading JTS from 4.0.5 to 4.0.6, when trying to load work items or create new ones, only a blank window with menu bar appears in RTC web client.
When using RTC eclipse client, the work item loads just fine.
Here is the stack trace:
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TypeError: _e[_d[i].slot] is undefined
File:
https://jazz.test.ru/ccm/web/_js/?exclude=H&include=com.ibm.team.workitem.web.ui.internal.page.WorkItemPageView&ss=EGtON&_proxyURL=%2Fccm&locale=ru
(Line: 74868)
Stack:
.sortSections@https://jazz.test.ru/ccm/web/_js/?exclude=H&include=com.ibm.team.workitem.web.ui.internal.page.WorkItemPageView&ss=EGtON&_proxyURL=%2Fccm&locale=ru:74868
.postCreate@https://jazz.test.ru/ccm/web/_js/?exclude=H&include=com.ibm.team.workitem.web.ui.internal.page.WorkItemPageView&ss=EGtON&_proxyURL=%2Fccm&locale=ru:74879
.create@https://jazz.test.ru/ccm/web/_js/?include=H~&etag=KBdzplhwVCP_ru&_proxyURL=%2Fccm&ss=EGtON&locale=ru:7172
.postscript@https://jazz.test.ru/ccm/web/_js/?include=H~&etag=KBdzplhwVCP_ru&_proxyURL=%2Fccm&ss=EGtON&locale=ru:7139
_38/<@https://jazz.test.ru/ccm/web/_js/?include=H~&etag=KBdzplhwVCP_ru&_proxyURL=%2Fccm&ss=EGtON&locale=ru:1067
._renderOverview@https://jazz.test.ru/ccm/web/_js/?exclude=H&include=com.ibm.team.workitem.web.ui.internal.page.WorkItemPageView&ss=EGtON&_proxyURL=%2Fccm&locale=ru:77827
._setPresentation@https://jazz.test.ru/ccm/web/_js/?exclude=H&include=com.ibm.team.workitem.web.ui.internal.page.WorkItemPageView&ss=EGtON&_proxyURL=%2Fccm&locale=ru:77755
._workingCopyInitialized@https://jazz.test.ru/ccm/web/_js/?exclude=H&include=com.ibm.team.workitem.web.ui.internal.page.WorkItemPageView&ss=EGtON&_proxyURL=%2Fccm&locale=ru:77502
.initializeWorkItemEditor@https://jazz.test.ru/ccm/web/_js/?exclude=H&include=com.ibm.team.workitem.web.ui.internal.page.WorkItemPageView&ss=EGtON&_proxyURL=%2Fccm&locale=ru:77467
._showWorkItemEditor@https://jazz.test.ru/ccm/web/_js/?exclude=H&include=com.ibm.team.workitem.web.ui.internal.page.WorkItemPageView&ss=EGtON&_proxyURL=%2Fccm&locale=ru:86569
.showWorkItemEditor@https://jazz.test.ru/ccm/web/_js/?exclude=H&include=com.ibm.team.workitem.web.ui.internal.page.WorkItemPageView&ss=EGtON&_proxyURL=%2Fccm&locale=ru:86560
.viewWorkItem@https://jazz.test.ru/ccm/web/_js/?exclude=H&include=com.ibm.team.workitem.web.ui.internal.page.WorkItemPageView&ss=EGtON&_proxyURL=%2Fccm&locale=ru:61376
.run@https://jazz.test.ru/ccm/web/_js/?include=H~&etag=KBdzplhwVCP_ru&_proxyURL=%2Fccm&ss=EGtON&locale=ru:18200
._runAction/<@https://jazz.test.ru/ccm/web/_js/?include=H~&etag=KBdzplhwVCP_ru&_proxyURL=%2Fccm&ss=EGtON&locale=ru:19020
_2@https://jazz.test.ru/ccm/web/_js/?include=H~&etag=KBdzplhwVCP_ru&_proxyURL=%2Fccm&ss=EGtON&locale=ru:17632
._runAction@https://jazz.test.ru/ccm/web/_js/?include=H~&etag=KBdzplhwVCP_ru&_proxyURL=%2Fccm&ss=EGtON&locale=ru:19019
._processActionUri/<@https://jazz.test.ru/ccm/web/_js/?include=H~&etag=KBdzplhwVCP_ru&_proxyURL=%2Fccm&ss=EGtON&locale=ru:18943
.viewPage@https://jazz.test.ru/ccm/web/_js/?include=H~&etag=KBdzplhwVCP_ru&_proxyURL=%2Fccm&ss=EGtON&locale=ru:18707
._processActionUri@https://jazz.test.ru/ccm/web/_js/?include=H~&etag=KBdzplhwVCP_ru&_proxyURL=%2Fccm&ss=EGtON&locale=ru:18942
._processUri@https://jazz.test.ru/ccm/web/_js/?include=H~&etag=KBdzplhwVCP_ru&_proxyURL=%2Fccm&ss=EGtON&locale=ru:18900
_10.hitch/<@https://jazz.test.ru/ccm/web/_js/?include=H~&etag=KBdzplhwVCP_ru&_proxyURL=%2Fccm&ss=EGtON&locale=ru:446
_10/</_17@https://jazz.test.ru/ccm/web/_js/?include=H~&etag=KBdzplhwVCP_ru&_proxyURL=%2Fccm&ss=EGtON&locale=ru:1317
on.emit@https://jazz.test.ru/ccm/web/_js/?include=H~&etag=KBdzplhwVCP_ru&_proxyURL=%2Fccm&ss=EGtON&locale=ru:1478
on.emit@https://jazz.test.ru/ccm/web/_js/?include=H~&etag=KBdzplhwVCP_ru&_proxyURL=%2Fccm&ss=EGtON&locale=ru:1511
_3.prototype.emit@https://jazz.test.ru/ccm/web/_js/?include=H~&etag=KBdzplhwVCP_ru&_proxyURL=%2Fccm&ss=EGtON&locale=ru:1697
.publish@https://jazz.test.ru/ccm/web/_js/?include=H~&etag=KBdzplhwVCP_ru&_proxyURL=%2Fccm&ss=EGtON&locale=ru:1706
_22.publish@https://jazz.test.ru/ccm/web/_js/?include=H~&etag=KBdzplhwVCP_ru&_proxyURL=%2Fccm&ss=EGtON&locale=ru:2462
_12@https://jazz.test.ru/ccm/web/_js/?include=H~&etag=KBdzplhwVCP_ru&_proxyURL=%2Fccm&ss=EGtON&locale=ru:18451
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One answer

There were some old CCM projects with custom work item attributes (fields) located on extra (hidden) editor presentation sections.
These sections did not have IDs, so the JavaScript failed when trying to render these sections with their content.
After moving the attributes to another section (e.g. Description), the problem disappeared.