The sparse-tree feature is very useful when you want to follow tasks of a specific project, and want to filter the whole org file to show only the relevant project tree. However, I did not find a way to apply this function to a specific tree at the cursor point. Sometimes, I want to act by project, and I know exactly where it is in the file, and I want to apply the sparse tree at this item, instead of searching by regexp, todo, etc. Is it possible?