In MDL-83008, a new constant, FEATURE_COMPLETION, was introduced to allow activity plugins to disable all completion features. However,  returning a false in the [PLUGINNAME]_supports only filters the plugin in a few pages.

This issue aims to make the FEATURE_COMPLETION consistent. When a plugin does not have completion, it should only return false to that constant and must be disabled everywhere.

This includes:

• The create activity form should not have completion fields.
• The bulk completion edit should not present the activities.
• The default completion forms should not display the plugin.
• All completion reports should not present the activities.

This issue could be divided into separate issues if necessary.

A bit of context

Since MDL-82617, some activities may not have completion (mod_subsection, for example). However, the completion functionality was validated using several feature contents like FEATURE_COMPLETION_TRACKS_VIEWS, FEATURE_COMPLETION_HAS_RULES and FEATURE_MODEDIT_DEFAULT_COMPLETION, but none of them is a natural way of disabling all completion features i a mod plugin.

One of the latest additions to the feature constants was FEATURECOMPLETION (MDL-83008). The constant was named this way because it is meant to be the correct way of disabling completion at a plugin level. However, at that moment, the priority was to fix a failed Q&A after the code freeze and implementing everywhere was out of scope.