Add sanity check for Gnus groups that belong to no topic

* lisp/gnus/gnus-topic.el (gnus-topic-change-level): Do not change
gnus-topic-alist when group is outside "topology" (bug#43582).

diff --git a/lisp/gnus/gnus-topic.el b/lisp/gnus/gnus-topic.el
index ffd26bb30f4c04205394df1d3b4feb5331a9cb3c..c913002f70bc118a7434e045c1360a795872e2a7 100644 (file)
--- a/lisp/gnus/gnus-topic.el
+++ b/lisp/gnus/gnus-topic.el
@@ -897,9 +897,7 @@ articles in the topic and its subtopics."
     (let ((inhibit-read-only t))
       (unless gnus-topic-inhibit-change-level
        (gnus-group-goto-group (or (car (nth 1 previous)) group))
-       (when (and gnus-topic-mode
-                  gnus-topic-alist
-                  (not gnus-topic-inhibit-change-level))
+       (when (and gnus-topic-mode gnus-topic-alist (gnus-current-topic))
          ;; Remove the group from the topics.
          (if (and (< oldlevel gnus-level-zombie)
                   (>= level gnus-level-zombie))