Keybinding oddness for `reopen closed tab` and quickscript-extra's `dynamic abbrevs`

The default keybinding for quickscript-extra's dynamic abbrev is currently c:s:t. This seems to have been the case since the birth of quickscript-extra in 2017-12 [1].

In 2022-04, it looks like DrRacket got support for Reopen Closed Tab, which IIUC, also has the keybinding c:s:t.

In my setup, once I installed quickscript-extra, invoking c:s:t triggered Reopen Closed Tab instead of dynamic abbrev. Unexpectedly, the dialog that comes up via "Edit" -> "Keybindings" -> "Show active keybindings" indicates that dynamic abbrev is associated with c:s:t. Further, I failed to locate Reopen Closed Tab via the dialog.

This situation is confusing to me (^^;

(Possibly worth noting is this PR to quickscript-extra.)

On a side note, is there some nice way to detect keybinding conflicts?

[1] These lines are from the first commit to quickscript-extra's repository.

Start with the referenced scripts/dynamic-abbrev.rkt lines and the linked DrRacket commit, then reproduce the conflict using Edit → Keybindings → Show active keybindings. Trace how both commands are registered and determine how the active binding and conflict reporting should behave; done means the two actions are no longer confusingly mapped and the behavior is covered or documented.