Pinned comments
A numbered pin on the board with a conversation behind it: a question about one resistor, answered in place, without typing anything into the circuit.
Putting one down
Press C and a pin lands under the pointer. Add a comment in the canvas toolbar's more menu puts one in the middle of the view. Either way the thread opens right away with the caret in the field, because a pin with nothing behind it says nothing.
Drop a pin over a part and it belongs to that part: drag the part across the board and the pin goes with it, which is what keeps "this one is the wrong value" on the thing it is about. Drop it on bare board and it stays where you put it. Drag a pin any time to move it.
The thread
Click a pin and the thread opens beside it: who wrote it, when, what it says, every reply under it, and a field to add one. Enter sends a reply and Shift+Enter starts a new line, because a reply is a line of talk rather than a document.
- Resolve marks the thread dealt with. Resolved pins are hidden, which is the whole point of resolving one. See below for how to read them again.
- Delete takes the thread away.
- Escape, the ×, or a click on empty board puts the thread away.
The pin's number is its place in the document, counting from one. Delete a thread and the ones after it renumber, so there are never gaps.
Whose name is on it
Signed in, a comment carries your account name. Signed out, in your own local project, it carries You. The editor works signed out and so does commenting in it. In a live room every comment carries the name of the account that wrote it, so a class can see who asked what.
Reading the resolved ones
Open the layers panel with L. The Comments row has a fourth switch, Show resolved, beside the usual show, dim and lock. Turn it on and the resolved pins come back, drawn grayed. The switch is this browser's view of this project, like the rest of the panel: it is not in the document and nobody else sees it change.
It is not a part
A comment carries no pins, is never wired, and is stored beside the parts rather than among them. The simulation never sees one: a board covered in pins builds exactly the netlist a bare one does.
A comment does not need the right to unlock, either. A student can pin a question to a locked starter circuit they may not touch, which is rather the point of an assignment with a question in it.
Everything else is ordinary
Undo takes back a comment you added, moved, wrote in, replied to, resolved or deleted. Deleting a part takes its own comments with it: the thread was about that part, and a pin with nothing under it says nothing.
Where they turn up
Comments travel with the document, so they are in the save, in a share link and on a project's page. In a live room a comment is an edit like any other: the pin appears on everybody's board as you put it down, and a reply appears in the thread they have open. See rooms.
They are not in a PNG or SVG export. A picture of a circuit is of the circuit; numbered pins are a conversation about it, and nobody wants them printed on a worksheet. See exporting PNG and SVG.