After a long dialog with various people in itslearning, it was suggested that i posted this here, for further consideration.

Currently your role in a hierarchy affects wether or not you have access by default to the plugins/extensions made available for your role.

Fx. a teacher who is a teacher in Hierarchy A has access to all the plugins/extensions (made available through 'standard availability') in courses under Hierarchy A.

If this teacher then has to assist in a course under Hierarchy B, another teacher can add her to the course, but since she isn't added to to Hierarchy B as a teacher but only the course, she won't have access to the plugins/extensions in that room by default anymore. She has to manually make these available to her, by adding them herself.

She is able to add them herself as long as the profile settings 'Allowed HTML Code Level' for teachers is set to 'Less restricted'. If this is changed to 'Restricted', then she is no longer able to add them by herself.

We strongly suggest to make this more transparent. If something is made available for teachers at organisation level through 'Standard availability', then it should be available to them by default and not be restricted to their role in the courses hierarchy.