Hi Gary,
I do not see the error you reported, but I am hoping stripping out that old code will resolve the issue you are seeing. Are you able to test this version and let us know if that helps:
https://gitlab.com/jezhops/moodle-theme_adaptable/-/archive/Moodle-3.9/moodle-theme_adaptable-Moodle-3.9.zip
Thanks
I do not see the error you reported, but I am hoping stripping out that old code will resolve the issue you are seeing. Are you able to test this version and let us know if that helps:
https://gitlab.com/jezhops/moodle-theme_adaptable/-/archive/Moodle-3.9/moodle-theme_adaptable-Moodle-3.9.zip
Thanks