Todowing
Focus sessions and time estimates for your Todoist Today view

Todowing is a Chrome extension that adds a planning layer to the Todoist web app. Pick tasks from Today, start a focus session with a countdown timer, and see time estimates add up in the Today header so you know whether the list fits the day. A notes pad sits above Today, and Apple Calendar events (read-only, up to five calendars) show next to your tasks. Sub-tasks at every depth appear in Today, Upcoming, Boards, Filters and Labels with their own dates, priorities and labels.
The free tier covers all sub-tasks, three focus sessions a week, seven color palettes and a text-size slider, with no account needed. A one-time $9.99 unlock adds unlimited focus sessions, time estimates, the notes pad, Apple Calendar, a font picker and sub-task editing. No subscription, and future updates are included.
It works on every Todoist plan, in the Todoist web app on Chrome. The extension talks straight to the Todoist API, so your tasks never touch Todowing servers, and it runs no analytics or tracking. Unofficial companion, not affiliated with Doist.