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Press S and click the board, or drag a sticky straight off the toolbar button. The toolbar’s colour picker sets the colour for new stickies: yellow, pink, blue, green or purple.
A new sticky starts in editing, ready to type (“Type something…”). To edit one later, select it and press Enter, or double-click it. Typing on a selected sticky doesn’t write into it: single keys are shortcuts (S for another sticky, Space to pan, ⇧ 1 to see everything), so you never add stray letters to someone else’s note. Esc or clicking away finishes. One stretch of typing is one undo step.
Pasting text that isn’t a link makes a sticky (up to 5000 characters).
A sticky can become an issue: select one or more and choose Make issues (⌥ I). The first line is the title and the rest is the body. When it’s pushed, the sticky turns into the new issue’s card in place. See Built-in actions.
In a section in silent mode, new stickies stay face down to everyone but their author until they’re revealed.
Press T and click anywhere to start typing. Text has four sizes (Small, Medium, Large and Extra large) and the same two typefaces, from the toolbar above it. Esc or ⌘ Enter finishes. Text you leave empty disappears.