Front end Editor-xtd error.

 HI there,
I really love Showtime Gallery thank you - I have been needing something like this for years! :-)

I am getting a red error in the front-end editing in 2 different websites on latest Joomla 4:

"Check-out failed with the following error: JLIB_APPLICATION_ERROR_NOT_EXIST"

This is showing in the xtd-buttons modal, just above the 'Save & Insert' and 'Use Existing' buttons.

Perhaps it is caused by this issue? https://issues.joomla.org/tracker/joomla-cms/35811 ?

The gallery seems to work as normal despite the error message.

Thank you,

Jen

I forgot to say, I am not getting the error in the administrator, only front end.

I am seeing this error also in the js console:

[Fine Uploader 5.15.4] GET request for sessionRefresh has failed - response code 500

Thanks.