-characters is what a key produced WITH modifiers applied; -charactersIgnoringModifiers is what it would have produced without them. This backend sent the same string for both, and xkbcommon applies the control transformation, so Control and A arrived as U+0001 in both. No binding for control plus a was ever found and the application inserted the control character into the document: the selection was replaced by an invisible character and the word count went to one. The bare string now comes from the keysym, which carries no modifier transformation. After the fix Control and A leaves the document alone and keeps the selection. Command and A already worked and now has a picture: docs/wayland-command-a-selects.png, where the status bar reads Selected: 4 words, 18 characters with the text highlighted. That is a modified shortcut going all the way from the compositor to the application, which nothing had tested before.