Failed to collect commits from repository ... An object with id ... could not be found

[9999years]

$ ~/gmap/target/release/gmap heat --interactive
Error: Failed to collect commits from repository

Caused by:
    0: Object find error: An object with id fdb30228b1dc649ab1c2086d146ef9dd0ab584e6 could not be found
    1: An object with id fdb30228b1dc649ab1c2086d146ef9dd0ab584e6 could not be found

Not sure what's happening here; it would be nice if the error message at least included the commit that the bad commit was found from.

[9999years]

Aha, it's submodules nonsense:

commit 7dcb77dd2cd46eee2c7d066fd9517eb658f87ce0
Author: Rebecca Turner <rbt@sent.as>
Date:   Thu Jul 13 12:24:53 2023 -0700

    update tpm

diff --git a/tmux/plugins/tpm b/tmux/plugins/tpm
index fdb3022..99469c4 160000
--- a/tmux/plugins/tpm
+++ b/tmux/plugins/tpm
@@ -1 +1 @@
-Subproject commit fdb30228b1dc649ab1c2086d146ef9dd0ab584e6
+Subproject commit 99469c4a9b1ccf77fade25842dc7bafbc8ce9946