Extend script crash when setting start/end on TrackItem

[seaanddogs]

When executing this simple code in Premiere 2020 (14.3.1 Build 45) :

var clip = app.project.activeSequence.videoTracks[0].clips[0];
clip.end = 12;

The end time of the clip changes properly but I get the error "Cannot set property end".

I tested the exact same code in Premiere 2019 (13.1.5 Build 47) and it changes the clip end without throwing any error...
Any idea why it does that ?

Many thanks

[seaanddogs]

I still get the same issue in Premiere 2020 (14.5.0.51).
Thanks

[guntramp26642460]

This is probably still tracked as DVAPR-4224243...
https://community.adobe.com/t5/premiere-pro/cannot-assign-values-to-trackitem-start-or-end/m-p/10973...