When run once on a todo item, records the time started at the beginning. When run a second time, replaces the start time with the time elapsed since the tag and the current time and tags the item as completed. Known bugs: the cursor may jump around. Does not validate that the text after "- started at" is correct.

Selects the next unfinished to-do item in the current page. The search starts after the current cursor location. Otherwise selects the first unfinished to-do item on the page.