Usually when I start to do something, then call
org-clock-in on task in Org Mode. Sometimes when changing tasks I forget to call
org-clock-in. How can I make
org-clock-out for the current task and
org-clock-in for the following with a custom time?
I am not aware of any such function that would allow you to stop the current clock and start a new one while adjusting the end and start times with a given value. I hope someone figures out how to write one.
Meanwhile your best option is to use org-clock-convenience package, https://github.com/dfeich/org-clock-convenience, that allows you to adjust clock times and then fill gaps between clocks. The catch is that tasks have to be visible in the org agenda.