Insert Symbol ran gnome-characters through PATH on Linux, which fails
where it is installed only as a Flatpak (#56); Windows ran charmap.exe
and macOS the Character Viewer. It now works as OneNote 2010 does
(Windows 7 lab, 2026-10-01): the Symbol button opens a gallery of the
20 symbols inserted lately, filled with OneNote's defaults, and More
Symbols opens a dialog with a search by Unicode name, a subset jump, a
grid of the characters the interface fonts draw, the recently used
row, and a character code field. Insert, Enter or a double click
inserts at the caret as an undo step of its own and leaves the dialog
open. Recent symbols persist in the settings. macOS keeps Emoji &
Symbols in the Edit menu.

Assisted-by: claude-opus-5.5