Text Annotations

Captions, reagent notes, and step numbers go on the canvas as text annotations: free-floating labels and fixed-size text boxes. You type straight into an in-place editor, and a formatting toolbar handles styling, from bold and subscripts to color and lists.

Placing text

Press T to activate the text tool.

Click an empty spot to place an auto-sizing text label and start typing. The label grows with its content and matches the current atom label font size.
Drag out a region more than 30 px wide or tall to create a fixed-size text box (at least 60 x 30 px). Boxes start with left alignment and the same font size as a clicked label.
While you drag out a box with smart guides on, its moving corner snaps to the edges and centres of other items, and the box lands where the preview showed it. Hold Ctrl to draw without snapping. A click-placed label does not snap. See Smart Guides.
Click an existing text annotation to open its editor; no new label is stacked on top.
Click an atom to edit that atom’s label. This is a separate editor from text annotations.
With the Select tool, select one text annotation and press Enter to open its editor.

The in-place editor

Typing happens directly in the rendered annotation, so what you see while editing is what renders on the canvas. The formatting toolbar appears at the top of the window while an editor is open.

Commit and cancel behavior:

Enter inserts a line break. Inside a list, Enter creates the next list item instead.
Ctrl+Enter commits the edit and closes the editor.
Clicking anywhere outside the editor also commits. With the Text tool, a click on empty canvas that finishes a text with content also returns you to the Select tool. A click away from a text that is still empty starts a new one at the click instead.
Opening and closing the editor without a change adds no undo step.
Escape closes the editor without keeping the session’s changes. If the annotation was just created and is still empty, Escape removes it.

Each edit session produces a single undo entry on the canvas. While the editor is open, Ctrl+Z and Ctrl+Y (or Ctrl+Shift+Z) step through formatting and typing changes within the session.

The toolbar applies formatting to the current selection, or sets up formatting at the cursor so the next characters you type inherit it. It offers:

Bold, italic, underline, strikethrough
Superscript and subscript, for charges and formula subscripts
Font family and font size pickers (see Fonts for adding fonts)
Text color and highlight (background color), both with live preview while you drag in the picker
Alignment: left, center, right
Bullet and numbered lists, plus a list style picker. Tab indents a list item and Shift+Tab outdents it.
Clear formatting, which strips bold/italic/underline/strikethrough and color/font styling from the selection but keeps sub/superscript and lists

Right-clicking inside the editor opens a context menu with Cut, Copy, Paste, Paste as plain text, Select all, Insert symbol, and Clear formatting.

While you type, the browser’s spellchecker underlines misspelled words. If the red underlines get in the way (chemical names trip them constantly), turn them off with Structure, then Spellcheck; the toggle applies to all text editing in the document and is on by default.

Symbol palette

The toolbar’s symbol button opens a palette with Greek letters, arrows, math and chemistry symbols, and Unicode subscript/superscript characters. Click a symbol to insert it at the cursor.

Backslash shortcuts such as \Delta and \hv expand only in arrow text zones (saved from either the inline editor or the properties panel), not in text annotations. For typeset math, use a LaTeX annotation instead.

Editor keyboard shortcuts

All verified in source.

Shortcut	Action
`Ctrl+B` / `Ctrl+I` / `Ctrl+U`	Bold / italic / underline
`Ctrl+Shift+X`	Strikethrough
`Ctrl+=`	Subscript
`Ctrl+Shift+=`	Superscript
`Ctrl+Shift+V`	Paste as plain text
`Ctrl+Enter`	Commit and close
`Escape`	Close without keeping changes
`Tab` / `Shift+Tab`	Indent / outdent in lists; outside a list, `Tab` moves focus to the toolbar

Editing, moving, and resizing

Double-click a text annotation with any tool (except pan) to reopen its editor. Double-clicking an already-selected atom edits its label (double-clicking an unselected atom selects its molecule first).
With the select tool, drag a text annotation to move it and drag the selection handles to resize it. Dragging a handle on an auto-sizing label converts it into a fixed-size box that starts from the size of its text and centres it; a click on a handle without a drag leaves the label as it was.
An auto-sizing label keeps its alignment as it grows: left-aligned text keeps its left edge, right-aligned text its right edge, and centred text stays centred.
A fixed-size box whose height fitted its text grows and shrinks with the text as you type. A box you made taller by hand keeps that height and only grows.
Hold Alt while you drag a text box to pull it free of the arrows drawn from it; hold Ctrl to move it without snapping while its arrows stay attached. See Select Tool.
A text box is either auto-sizing (it hugs its content, and shows a small auto badge in its corner when selected) or fixed-size (you gave it an explicit size by dragging a resize handle, as above).
Right-click a fixed-size text box for Shrink to Text (tighten the box around its content) or Make Auto-size (drop the fixed width and height, returning the box to auto-sizing). These two options do not appear for an auto-sizing box, since it is already shrink-wrapped to its text. Ctrl+double-clicking one of a fixed-size box’s resize handles performs the same shrink-to-fit. A plain double-click on a handle opens the editor instead. Every double-click target is listed in Double-click shortcuts.