Prevent accidental task completion

For someone like me with a lot of experience using this awesome app, this is not an issue because I'm always aware I can mark a task as complete with a simple click on the left circle. I'm using tasks as categories, so an accidental click has the potential to hide(and practically delete) something with dozens of tasks. This is potentially a problem when sharing a project with people with little or no experience - they can hide(=delete) important things just by browsing task organized on many levels and I wouldn't notice that - the open/collapse icon is only 10-15 pixels away from a dangerous button(the "complete" circle). Quire already added a safety feature when deleting a project(force type the project name). My suggestion is to add some sort of delay for complete button. It's incredibly easy to hide tasks+categories by accident. This can also apply to delete button. A practical solution I think it's user friendly and consistent with Quire look&feel: mouse press the circle for more than one second and release it after a visual cue like a loading animation.