keybind-find reads the shortcuts you actually configured, then runs the one you pick
keybind-find searches shortcuts for the focused Linux window and supported desktop settings. On supported setups, selecting a result sends the keys for you.
The shortcut exists. Your memory of it has apparently been garbage-collected. keybind-find opens a searchable list built around the app you are using, including supported custom bindings.
Its README describes reading real configurations rather than asking you to maintain a second cheat sheet. Select an action and it can send the corresponding keys, while also showing what you could press next time.
The compatibility table deserves the click before installation. KDE Plasma on Wayland lists shortcuts but does not send selected keys. GNOME on Wayland also cannot send picks and opens its list in fzf. Support differs by window manager and app; “universal” would promise too much.
The next shortcut worth learning may be the one that opens the list. After that, the app can show whether your own configuration is as memorable as you thought.