Record your screen, then edit it on a timeline that shows where something happens and where nothing does, so the slow parts can be squeezed or cut in one go. Add a magnifier, focus, arrows and counters to recordings and screenshots, and copy text from any part of the screen. Recording, editing, screenshots and text recognition are free and open source, for macOS and Windows. Ruler, Annotate, Glide and References are paid tools, each free for 14 days.
Notion, Jira, Trello, even Todoist and Things are all overdone. They want projects, onboarding, and setup before you can write down a single thought, and keeping them tidy becomes its own chore.
Overdone goes the other way. Click it, start typing, that's it. As quick to jot in as a sticky note, as capable as you need when a task actually earns it.