Task Manager is a promoted attributes and scripts showcase present in the demo document.

Task Manager manages outstanding (TODO) tasks and finished tasks (non-empty doneDate attribute). Outstanding tasks are further categorized by location and arbitrary tags - whenever you change tag attribute in the task note, this task is then automatically moved to appropriate location.

Task Manager also integrates with day notes - notes are cloned into day note to both todoDate note and doneDate note (with prefix of either "TODO" or "DONE").

New tasks are created in the TODO note which has ~child:template relation (see attribute inheritance) pointing to the task template.

Task template defines several promoted attributes - todoDate, doneDate, tags, location. Importantly it also defines ~runOnAttributeChange relation - event handler which is run on attribute change. This script handles when e.g. we fill out the doneDate attribute - meaning the task is done and should be moved to "Done" note and removed from TODO, locations and tags.

There's also "button" note which contains simple script which adds a button to create new note (task) in the TODO note.

api.addButtonToToolbar({
    title: 'New task',
    icon: 'check',
    shortcut: 'alt+n',
    action: async () => {
        // creating notes is backend (server) responsibility so we need to pass
        // the control there
        const taskNoteId = await api.runOnBackend(async () => {
            const todoRootNote = await api.getNoteWithLabel('taskTodoRoot');
            const {note} = await api.createNote(todoRootNote.noteId, 'new task', '');

            return note.noteId;
        });

        // we got an ID of newly created note and we want to immediatelly display it
        await api.activateNewNote(taskNoteId);
    }
});

In the demo screenshot above you may notice that TODO tasks are in red color and DONE tasks are green.

This is done by having this CSS code note which defines extra CSS classes:

span.fancytree-node.todo .fancytree-title {
    color: red !important;
}

span.fancytree-node.done .fancytree-title {
    color: green !important;
}

This code note has #appCss label which is recognized by Trilium on startup and loaded as CSS into the application.

Second part of this functionality is based in event handler described above which assigns #cssClass label to the task to either "done" or "todo" based on the task status.