This issue is part of the course hierarchy epic.

Currently, sections' collapsed states are stored as standard user preferences. This generates a problem for extensive courses (MDL-78073). With the introduction of subsections (using mod_subsection), we can store the subsection preference in a different user preference value. This can help mitigate the problem and also be a potential performance improvement.

Issue goals

Evaluate if storing mod_subsection preferences as a different user preference can improve the course view performance for long courses.

Implement a pull request to the mod_subsection project with the changes.

Future issues

In the next issues, mod_subsection will be incorporated into the core. Having those changes will help.