Uncaught TypeError: Cannot read property 'length' of undefined for ace2_common.js?callback=require.define&v=bff27219

[q2apro]

Describe the bug
Opening the revision history breaks the page and the error appears:

An error occurred
Please press and hold Ctrl and press F5 to reload this page
If the problem persists, please send this error message to your webmaster:
TypeError: Uncaught TypeError: Cannot read properties of undefined (reading 'length')
at https://DOMAIN/javascripts/lib/ep_etherpad-lite/static/js/ace2_common.js?callback=require.define&v=e921c6f3 at line 29
ErrorId: G3HSbZuwQFqXoUe1x4yE
Uncaught exception
URL: https://DOMAIN/p/myetherpad/timeslider#1482
UserAgent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/129.0.0.0 Safari/537.36

Expected behavior
Revision history shows up.

Screenshots

Server (please complete the following information):

• Etherpad version: 1.9.6
• OS: Ubuntu 20.04
• Is the server free of plugins: no, plugin ep_tableau 1.1.1 is used from https://www.npmjs.com/package/ep_tableau

Additional context
In the etherpad I see that the users created a table and there is a fragment of the table plugin showing up with {"payload":[[".

I assume that the syntax of the table plugin has something inside that kills the revision history of the core.

The core code should be checked and this bug eliminated. 🙂

Here an excerpt from the etherpad with the issue:

{"payload":[[" Thema des Angebots"]],"tblId":"1","tblClass":"data-tables", "tblProperties":{"borderWidth":"1","cellAttrs":[],"width":"100","rowAttrs":{},"colAttrs":[],"authors":{},"isFirstRow":true}}
{"payload":[[" KI im Unterricht einsetzen"]],"tblId":"1","tblClass":"data-tables", "tblProperties":{"borderWidth":"1","cellAttrs":[],"width":"100","rowAttrs":{},"colAttrs":[],"authors":{}}}
{"payload":[[" Zuordnung zum Erlass"]],"tblId":"1","tblClass":"data-tables", "tblProperties":{"borderWidth":"1","cellAttrs":[],"width":"100","rowAttrs":{},"colAttrs":[],"authors":"a.vjh0thCYkxhLDP9W"}}
{"payload":[["  - Lehren und Lernen in der digitalen Welt /r/n - Medienkonzeptentwicklung /r/n - Lernförderlicher Einsatz digitaler Medien /r/n - Rechtssichere Nutzung digitaler Medien /r/n  
1.2 -- zur lernförderlichen IT-Ausstattung
1.3 -- zur Anwendung sowie zum lernförderlichen Einsatz
1.4 -- zu Grundlagen einer verantwortungsvollen und rechtssicheren Nutzung digitaler Medien und Geräte wie zum Beispiel: 1.4.3 --- Open Education Ressources (OER)
1.7 -- zur Umsetzung des Medienkompetenzrahmens 
6 Unterstützung bei Evaluationsvorhaben im Kontext
"]],"tblId":"1","tblClass":"data-tables", "tblProperties":{"borderWidth":"1","cellAttrs":[],"width":"100","rowAttrs":{},"colAttrs":[],"authors":{}}}
{"payload":[[" Ziel"]],"tblId":"1","tblClass":"data-tables", "tblProperties":{"borderWidth":"1","cellAttrs":[],"width":"100","rowAttrs":{},"colAttrs":[],"authors":"a.vjh0thCYkxhLDP9W"}}
{"payload":[["
Ziel einer Beratungsveranstaltung zum Thema 'KI im Unterricht einsetzen' ist es,....
"]],"tblId":"1","tblClass":"data-tables", "tblProperties":{"borderWidth":"1","cellAttrs":[],"width":"100","rowAttrs":{},"colAttrs":[],"authors":{}}}
{"payload":[[" Prozess und Prozessschritte"]],"tblId":"1","tblClass":"data-tables", "tblProperties":{"borderWidth":"1","cellAttrs":[],"width":"100","rowAttrs":{},"colAttrs":[],"authors":"a.vjh0thCYkxhLDP9W"}}
{"payload":[[" - Bedarfe ermitteln und Feinziele planen - gemeinames Verständnis und Zielklarheit"]],"tblId":"1","tblClass":"data-tables", "tblProperties":{"borderWidth":"1","cellAttrs":[],"width":"100","rowAttrs":{},"colAttrs":[],"authors":"a.vjh0thCYkxhLDP9W"}}
{"payload":[[" 
Um die Bedürfnisse und Feinziele für ein Beratungsangebot zum Thema 'KI im Unterricht' zu ermitteln und Zielklarheit zu schaffen, eignen sich z.B. folgende Karten des KOMPASS-Kartensets
1. Lernkultur (rot)
2. Lehr- und Lernsettings (rot)
3. (Medien-)Didaktik (pink)
4.  Haltungen (pink)
5. Medienkonzept (grün)
6. Fortbildungsplanung (pink)
...

{"payload":[[" Veröffentlichungstext - Thematische Schwerpunkte"]],"tblId":"1","tblClass":"data-tables", "tblProperties":{"borderWidth":"1","cellAttrs":[],"width":"100","rowAttrs":{},"colAttrs":[],"authors":{}}}
{"payload":[[" aus dem oben Genanntem entwickeln /r/n  /r/n  /r/n "]],"tblId":"1","tblClass":"data-tables", "tblProperties":{"borderWidth":"1","cellAttrs":[],"width":"100","rowAttrs":{},"colAttrs":[],"authors":{"a.vjh0thCYkxhLDP9W":{"row":0,"cell":0,"colorId":"#c7d5ff"}}}}

Here is the full etherpad export. It is 373 KB, so I guess the revision history is inside:
export-etherpad.zip